Note: This page contains sample records for the topic short communication high from Science.gov.
While these samples are representative of the content of Science.gov,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of Science.gov
to obtain the most current and comprehensive results.
Last update: November 12, 2013.
1

Treatment of cigarette smoking with short-term high-dosage corticotrophin therapy: preliminary communication.  

PubMed Central

Uncontrolled studies have indicated that the smoker's "life' can be simulated clinically by short-term, high-dosage corticotrophin therapy. Following such treatment, smokers previously prevented by the withdrawal syndrome from giving up smoking were able to do so easily. All 10 patients reported here were still not smoking after seven months.

Bourne, S

1985-01-01

2

Automatic short-pulse reshaping for high-speed optical communication systems  

NASA Astrophysics Data System (ADS)

For the next-generation ultra-high-speed TDM optical communication systems, we are developing a waveguide type digital optical pulse synthesizer based on the time-to-space conversion. Our digital optical synthesizer can produce arbitrary optical packets with high bit rate in the order of 100 Gbps and chirp-free pulses. In the early prototype, the signal for controlling the phase and the amplitude of optical signal was manually adjusted with trial and error. Recently, we have introduced a feedback system to this synthesizer for automatic generation of controlling signal, which makes it extremely easier to produce optical signal with arbitrary shape. In this paper, we demonstrate experimental generation of Fourier-transform limited optical pulses and arbitrary 8-bit RZ pulse packets with a bit rate of 100 Gbps.

Tanaka, Yosuke; Kurokawa, Takashi

2007-11-01

3

Short communications in the astronomical literature  

NASA Astrophysics Data System (ADS)

The tendency is noted for short, high-priority communications in the literature (Letters or Research Notes) to become longer with time. This trend occurs despite external controls (fixed page limits) and mimics the same trend noted for the astronomical literature in general (Abt 1981).

Harris, W. E.

1983-12-01

4

Short Communication: Carora Cattle Show High Variability in ?s1Casein  

Microsoft Academic Search

Theobjectiveofthisstudywastoanalyzethegenetic variability of milk proteins of the Carora, a short- horned Bos taurus cattle breed in Venezuela and in other Southern American countries that is primarily used formilk production.A totalof 184individual milk samples were collected from Carora cattle in 5 herds in Venezuela. The milk protein genes ?s1-casein (CN) (CSN1S1), ?-CN (CSN2), ?-CN (CSN3), and ?-lacto- globulin (LGB) were typed

A. Caroli; S. Chessa; F. Chiatti; D. Rignanese; B. Meléndez; R. Rizzi; G. Ceriotti

2008-01-01

5

SHORT COMMUNICATION: Metal carbide-carbon peritectic systems as high-temperature fixed points in thermometry  

NASA Astrophysics Data System (ADS)

WC-C, Cr3C2-C and Mn7C3-C peritectic systems were investigated for their potential of serving as high-temperature reference points in thermometry. Mixtures of high-purity graphite powder with W, Cr and Mn powder of 99.99%, 99.9% and 99.95% purity by mass, respectively, were placed in graphite blackbody crucibles and melting/freezing plateaus were observed by means of a radiation thermometer. The observed melting temperatures were 2749 °C (WC-C), 1826 °C (Cr3C2-C) and 1331 °C (Mn7C3-C), with a repeatability—in each case—of 0.02 K. The melting range for WC-C and Cr3C2-C peritectics was roughly 0.1 K. WC-C showed a flat freezing plateau that agreed with the melting plateau within the repeatability. The three fixed points are possible candidates, like the metal (carbide)-carbon eutectic fixed points, in the realization of an improved high-temperature scale above the copper point.

Yamada, Y.; Wang, Y.; Sasajima, N.

2006-10-01

6

Short communication: Carora cattle show high variability in alpha(s1)-casein.  

PubMed

The objective of this study was to analyze the genetic variability of milk proteins of the Carora, a shorthorned Bos taurus cattle breed in Venezuela and in other Southern American countries that is primarily used for milk production. A total of 184 individual milk samples were collected from Carora cattle in 5 herds in Venezuela. The milk protein genes alpha(s1)-casein (CN) (CSN1S1), beta-CN (CSN2), kappa-CN (CSN3), and beta-lactoglobulin (LGB) were typed at the protein level by isoelectrofocusing. It was necessary to further analyze CSN1S1 at the DNA level by a PCR-based method to distinguish CSN1S1*G from B. Increased variation was found in particular at the CSN1S1 gene, where 4 variants were identified. The predominant variant was CSN1S1*B (frequency = 0.8). The second most common CSN1S1 variant was CSN1S1*G (0.101), followed by CSN1S1*C (0.082). Moreover, a new isoelectrofocusing pattern was identified, which may result from a novel CSN1S1 variant, named CSN1S1*I, migrating at an intermediate position between CSN1S1*B and CSN1S1*C. Six cows carried the variant at the heterozygous condition. For the other loci, predominance of CSN2*A2 (0.764), CSN3*B (0.609), and LGB*B (0.592) was observed. Haplotype frequencies (AF) at the CSN1S1-CSN2-CSN3 complex were also estimated by taking association into account. Only 7 haplotypes showed AF values >0.05, accounting for a cumulative frequency of 0.944. The predominant haplotype was B-A2-B (frequency = 0.418), followed by B-A2-A (0.213). The occurrence of the G variant is at a rather high frequency, which is of interest for selection within the Carora breed because of the negative association of this variant with the synthesis of the specific protein. From a cheese-making point of view, this variant is associated with improved milk-clotting parameters but is negatively associated with cheese ripening. Thus, milk protein typing should be routinely carried out in the breed, with particular emphasis on using a DNA test to detect the CSN1S*G variant. The CSN1S*G allele is likely to have descended from the Brown Swiss, which contributed to the Carora breed and also carries this allele. PMID:18096958

Caroli, A; Chessa, S; Chiatti, F; Rignanese, D; Meléndez, B; Rizzi, R; Ceriotti, G

2008-01-01

7

A secure short message communication protocol  

Microsoft Academic Search

According to the security requirement of the short message service (SMS) industry application, a secure short message communication\\u000a protocol is proposed. This is an application level protocol constructed on the standard SMS communication protocol using public\\u000a key authentication and key agreement without the need of wireless public key infrastructure (WPKI). Secure short message transmission\\u000a and dynamic key agreement between mobile

Chao-Wen Chang; Heng Pan; Hong-Yong Jia

2008-01-01

8

Short Communication: Inactivation of Microbial Contaminants in Raw Milk La Serena Cheese by High-Pressure Treatments  

Microsoft Academic Search

La Serena cheese, a Spanish variety made from Me- rino ewes' raw milk, has a high pH value, low salt con- tent, and high moisture, conditions that are all favorable for growth and survival of contaminating microorgan- isms, including pathogens. To improve its microbiologi- cal quality and safety, high-pressure treatments at 300 or 400 MPa for 10 min at 10°C

J. L. Arqués; S. Garde; P. Gaya; M. Medina; M. Nuñez

2006-01-01

9

Short Communication Spatial variability of the Caribbean mid-summer drought and relation to north Atlantic high circulation  

Microsoft Academic Search

ABSTRACT: Annual rainfall in the Caribbean exhibits a bimodal,structure with two,rainfall maxima,(May–June and September–October) separated by what has been termed,a mid-summer,drought (MSD) (July–August). Despite general acceptance of the intensification and expansion,of the North Atlantic High Pressure (NAHP) as the cause of the Caribbean MSD, it has been noted in several studies that the influence of the NAHP may not be

Douglas W. Gamble; Darren B. Parnell; Scott Curtis

10

High Voltage AC Power Transmission Lines and Communications Receiver Sites.  

National Technical Information Service (NTIS)

A short discussion of the effects of the Electromagnetic Interference (EMI) radiated from High Voltage AC (HVAC) Power Transmission lines on HF Communications Receivers is followed by the description of a method for choosing communications receiver sites ...

F. R. Hill

1976-01-01

11

Short communication Baboons communicate with their right hand  

Microsoft Academic Search

Humans are mainly right-handed for many actions including gestures. This bias is strongly linked to a left cerebral hemispheric dominance for language functions. Whether similar lateralized systems for communicative behaviors are present in other animals is unclear. Here we report the first evidence of strong population-level right-handedness in 60 captive baboons for a species-specific communicative manual gesture. Our findings support

Adrien Meguerditchian; Jacques Vauclair

12

The Global System for Mobile Communications Short Message Service  

Microsoft Academic Search

This tutorial presents an overview of the Global System for Mobile Communications Short Message Service from the viewpoint of implementing new telematic services. The SMS offers the users of GSM networks the ability to exchange alphanumeric messages up to the limit of 160 characters. The tutorial is motivated by an acute absence of research publications in this field. The information

C. Peersman; S. Cvetkovic; P. Griffiths; H. Spear

2000-01-01

13

Brevity is prevalent in bat short-range communication.  

PubMed

Animal communication follows many coding schemes. Less is known about the coding strategy for signal length and rates of use in animal vocal communication. A generalized brevity (negative relation between signal length and frequency of use) is innovatively explored but remains controversial in animal vocal communication. We tested brevity for short-range social and distress sounds from four echolocating bats: adult black-bearded tomb bat Taphozous melanopogon, Mexican free-tailed bat Tadarida brasiliensis, adult greater horseshoe bat Rhinolophus ferrumequinum, and adult least horseshoe bat Rhinolophus pusillus. There was a negative association between duration and number of social but not distress calls emitted. The most frequently emitted social calls were brief, while most distress calls were long. Brevity or lengthiness was consistently selected in vocal communications for each species. Echolocating bats seem to have convergent coding strategy for communication calls. The results provide the evidence of efficient coding in bat social vocalizations, and lay the basis of future researches on the convergence for neural control on bats' communication calls. PMID:23377576

Luo, Bo; Jiang, Tinglei; Liu, Ying; Wang, Jing; Lin, Aiqing; Wei, Xuewen; Feng, Jiang

2013-02-02

14

Semiconductor device as optical demultiplexer for short range optical communications.  

PubMed

In this paper we present results on the use of a multilayered a-SiC:H heterostructure as a wavelength-division demultiplexing device for the visible light spectrum. The proposed device is composed of two stacked p-i-n photodiodes with intrinsic absorber regions adjusted to short and long wavelength absorption and carrier collection. An optoelectronic characterisation of the device was performed in the visible spectrum. Demonstration of the device functionality for WDM applications was done with three different input channels covering the long, the medium and the short wavelengths in the visible range. The recovery of the input channels is explained using the photo-current spectral dependence on the applied voltage. An electrical model of the WDM device is proposed and supported by the solution of the respective circuit equations. Short range optical communications constitute the major application field, however other applications are also foreseen. PMID:21770182

Louro, P; Vieira, M; Fernandes, M; Vieira, M A; Costa, J; Fantoni, A

2011-06-01

15

Evidence for short-range sonic communication in lymantriine moths.  

PubMed

Sexual communication of nun moth, Lymantria monacha (L.), pink gypsy moth, Lymantria mathura Moore, and fumida tussock moth, Lymantria fumida Butler (all Lepidoptera: Noctuidae: Lymantriinae), is known to be mediated by pheromones. We now show that males are attracted by the sounds of conspecific females over short distances and that wing fanning male and female L. monacha, L. mathura and L. fumida produce species- and sex-specific wing beat and associated click sounds that could contribute to reproductive isolation. Evidence for short-range communication in these lymantriines includes (i) scanning electron micrographs revealing metathoracic tympanate ears, (ii) laser interferometry showing particular sensitivity of tympana tuned to frequency components of sound signals from conspecifics, and (iii) phonotaxis of male L. monacha and L. fumida to speakers playing back sound signals from conspecific females. We conclude that tympanate ears of these moths have evolved in response not only to bat predation, but also for short-range mate finding and possibly recognition. PMID:21115014

Rowland, E; Schaefer, P W; Belton, P; Gries, G

2010-11-27

16

When the facts are just not enough: Credibly communicating about risk is riskier when emotions run high and time is short  

SciTech Connect

When discussing risk with people, commonly subject matter experts believe that conveying the facts will be enough to allow people to assess a risk and respond rationally to that risk. Because of this expectation, experts often become exasperated by the seemingly illogical way people assess personal risk and choose to manage that risk. In crisis situations when the risk information is less defined and choices must be made within impossible time constraints, the thought processes may be even more susceptible to faulty heuristics. Understanding the perception of risk is essential to understanding why the public becomes more or less upset by events. This article explores the psychological underpinnings of risk assessment within emotionally laden events and the risk communication practices that may facilitate subject matter experts to provide the facts in a manner so they can be more certain those facts are being heard. Source credibility is foundational to risk communication practices. The public meeting is one example in which these best practices can be exercised. Risks are risky because risk perceptions differ and the psychosocial environment in which risk is discussed complicates making risk decisions. Experts who want to influence the actions of the public related to a threat or risk should understand that decisions often involve emotional as well as logical components. The media and other social entities will also influence the risk context. The Center for Disease Control and Prevention's crisis and emergency-risk communication (CERC) principles are intended to increase credibility and recognize emotional components of an event. During a risk event, CERC works to calm emotions and increase trust which can help people apply the expertise being offered by response officials.

Reynolds, Barbara J., E-mail: Bsr0@cdc.gov

2011-07-15

17

Short communication: high natural polymorphism in the gag gene cleavage sites of non-B HIV type 1 isolates from Gabon.  

PubMed

The main goal of the present study was to determine the frequency of substitutions in the cleavage sites (CS) of gag gene among non-B HIV-1 isolates from Gabon. Fifty plasma specimens, collected in 2010-2011, from HIV-1-infected patients failing first-line antiretroviral (ARV) regimens (constituted of two nucleoside reverse transcriptase inhibitors+one nonnucleoside reverse transcriptase inhibitor) (n=38) and from HIV-1-infected individuals untreated with ARV (n=12) were analyzed in the gag and gag-pol cleavage sites. Compared to HXB2 reference sequence, the total median number of substitutions in gag and gag-pol CS was 10 (range, 5-18). The cleavage site p2/NC was the most variable of the four gag CS with 100% (50/50) isolates carrying at least 1 substitution (range, 1-9). The two gag-pol TFP/p6pol and p6pol/PR CS sites were also highly variable (at least one substitution, 50/50, 100% in both cases). Substitutions at position G381 (p2/NC), L449 (p1/p6gag), and K444 (TFP/p6pol) were significantly more frequent in CRF02_AG strains, compared to other non-B strains (30.4% vs. 3.7%, p=0.03; 87.0% vs. 59.3%, p=0.03; and 91.3% vs. 59.3%, p=0.01, respectively). Other non-B subtypes were significantly more likely to harbor substitutions at position N487 (p6pol) (70.4%) than CRF02_AG (39.1%) (p=0.02). In Gabon, gag and gag-pol cleavage sites were highly polymorphic in protease inhibitor-naive patients harboring non-B HIV-1 strains. In sub-Saharan Africa, further studies are definitively required to better understand the impact of gag mutations among subjects receiving second-line LPV/r-containing regimens (monotherapy or triple combinations). PMID:23551028

Liégeois, Florian; Reteno, Dorine Gaëlle Ikanga; Mouinga-Ondémé, Augustin; Sica, Jeanne; Rouet, François

2013-04-30

18

Short communication: Responses to supplemental Saccharomyces cerevisiae fermentation product and triticale grain in dairy cows grazing high-quality pasture in early lactation.  

PubMed

Supplementing cows grazing highly digestible pasture with a Saccharomyces cerevisiae fermentation product (SCFP) was hypothesized to increase dry matter (DM) intake and milk production. Sixty multiparous dairy cows were fed 3 kg of crushed triticale DM/cow per day for 23 ± 4.4 d before calving. Half of the cows received SCFP (60 g/d; Diamond V Original XP; Diamond V Mills, Inc., Cedar Rapids, IA). Cows in both treatment groups were randomly allocated at calving to 1 of 2 amounts (3 or 6 kg of DM/d) of triticale feeding with or without 60 g of SCFP/day (n=15/treatment) until 84 days in milk. The amount of pasture harvested (kg of DM/cow per day) and milk yield (kg/cow per day) were not affected by SCFP. Milk protein content and yield were greater in cows receiving 6 kg of crushed triticale DM/d. Plasma nonesterified fatty acids and ?-hydroxybutyrate concentrations were not affected by SCFP supplementation, but were lower in cows fed 6 kg of crushed triticale DM/d than those fed 3 kg of DM/d. Supplementation with SCFP increased milk lactose content without affecting milk production under the conditions investigated. PMID:21605780

Irvine, L D; Freeman, M J; Donaghy, D J; Yoon, I; Lee, G; Roche, J R

2011-06-01

19

High bandwidth underwater optical communication.  

PubMed

We report error-free underwater optical transmission measurements at 1 Gbit/s (10(9) bits/s) over a 2 m path in a laboratory water pipe with up to 36 dB of extinction. The source at 532 nm was derived from a 1064 nm continuous-wave laser diode that was intensity modulated, amplified, and frequency doubled in periodically poled lithium niobate. Measurements were made over a range of extinction by the addition of a Mg(OH)(2) and Al(OH)(3) suspension to the water path, and we were not able to observe any evidence of temporal pulse broadening. Results of Monte Carlo simulations over ocean water paths of several tens of meters indicate that optical communication data rates >1 Gbit/s can be supported and are compatible with high-capacity data transfer applications that require no physical contact. PMID:18188210

Hanson, Frank; Radic, Stojan

2008-01-10

20

A Short Guide to EU Grants for Science Communication  

NASA Astrophysics Data System (ADS)

"The importance of communicating science to the general public cannot be overestimated. Science cannot live isolated from society." As the words of Janez Potocnik, EU Science and Research Commissioner, clearly demonstrate, there is a political call to the European Union (EU) for supporting science communication. But as we all know, the reality lies in the implementation and not in the mission statements. So let's see what the EU can offer to science communicators.

Patkós, E.

2008-02-01

21

Short pulse high voltage systems  

Microsoft Academic Search

The design features of current high speed pulse electron beam generators are outlined. The development of multi-channel switching is briefly reviewed. The inductance of the vacuum envelope and its immediate feeds presents a limit to the pulse rise time in low impedance systems and some present day limits are indicated. Within the diode the energy can be carried by a

J. C. Martin

1976-01-01

22

Diffuse high-bandwidth optical communications  

Microsoft Academic Search

High speed underwater optical communications has at least three distinct advantages over acoustic communications. The data rates achievable are high (1 to 10 Mbps), the latency from when data is sent to when data is received is low, and there is no acoustic noise associated with transmission. Of course one of the biggest limitations of an optical approach underwater is

Clifford Pontbriand; Norman Farr; Jonathan Ware; James Preisig; Hugh Popenoe

2008-01-01

23

ISS Update: High Rate Communications System  

NASA Video Gallery

ISS Update Commentator Pat Ryan interviews Diego Serna, Communications and Tracking Officer, about the High Rate Communications System. Questions? Ask us on Twitter @NASA_Johnson and include the hashtag #askStation. For the latest news about the space station, visit http://www.nasa.gov/station.

Mark Garcia

2012-03-27

24

Communication with reentry space vehicles via short pulses  

Microsoft Academic Search

The resonant absorption of a short pulse of electromagnetic radiation in a plasma slab is considered in order to examine the effectiveness of using short pulses for information transfer through the plasma sheaths surrounding reentry vehicles. The amplitudes of the Raman scattering (RS) on the Langmuir oscillations associated with resonant absorption and the amplitude of the Brillouin scattering (BS) on

Sergey V. Nazarenko; Alan C. Newell; Alexander M. Rubenchik

1995-01-01

25

Short Messaging Services using TDRSS with low-power Personal Communication Devices  

Microsoft Academic Search

The Tracking and Data Relay Satellite (TDRS) and the TDRS System (TDRSS) form the basis for NASA's Space Network (SN) originally intended for manned spaceflight communications. While admirably serving this function, the TDRSS can also provide alternate communications for a variety of low-power operational requirements. This includes the use of Short Messaging Services (SMS) with personal-sized devices where small amounts

Jerry Brand

2011-01-01

26

Memorable Messages of Hard Times: Constructing Short and Long-Term Resiliencies Through Family Communication  

Microsoft Academic Search

We take a communicative and life course theory approach to understanding how resilience is constructed in families. Drawing upon interviews with 20 fathers, 16 mothers, and 23 children who dealt with financial hardship during the 1980s recession, we analyze the messages families communicated about finances when their children were young and how these messages contributed to the development of short-

Kristen Lucas; Patrice M. Buzzanell

2012-01-01

27

Using short stories to teach critical thinking and communication skills to tax students  

Microsoft Academic Search

Researchers and numerous groups stress the importance of incorporating communication skills development into accounting curricula. Although a number of formal and informal techniques are available to instructors to incorporate writing skills into the classroom, many students have both oral and writing communication apprehension (CA). Short stories are a flexible teaching tool to overcome boredom both inside and outside the classroom.

D. Larry Crumbley; L. Murphy Smith

2000-01-01

28

10-Mbps Short-Range Baseband Wireless Communications via Quasi-Static Electric Fields  

Microsoft Academic Search

We propose a novel short-range wireless communications technology that uses quasi-static electric fields; it enables data communication between devices separated by up to 10cm via dielectric media at a speed of 10Mbps. It is considered to be a secure wireless technology since communication area is restricted to below about 10cm. To suppress electromagnetic radiation, we adopted a baseband transmission scheme

Ai-Ichiro Sasaki; Akinori Furuya; Mitsuru Shinagawa

2010-01-01

29

How to Write a Long Formula (Short Communication)  

Microsoft Academic Search

Standard mathematical notation works well for short formulas, but not for the longer ones often written by computer scientists. Notations are proposed to make one or two-page formulas easier to read and reason about.

Leslie Lamport

1994-01-01

30

Short-Wave Aviation Communication Signal Analysis and Aircraft Classification  

Microsoft Academic Search

This paper investigates how to classify the type of the aircraft based on the aviation communication signal. Hilbert-Huang Transform (HHT) is introduced to adaptively decompose the cockpit voice into several IMFs, then the IMFs can be used as the features of the aircraft for identifying the type. To alleviate the problem of mode mixing caused by the signal intermittency in

Liu Feng; Li Xueyao; Liang Zhilan

2008-01-01

31

Green Codes: Energy-Efficient Short-Range Communication  

Microsoft Academic Search

A green code attempts to minimize the total en- ergy per-bit required to communicate across a noisy channel. The classical information-theoretic approach neglects the energy expended in processing the data at the encoder and the decoder and only minimizes the energy required for transmissions. Since there is no cost associated with using more degrees of freedom, the traditionally optimal strategy

Pulkit Grover; Anant Sahai

2008-01-01

32

High current short pulse ion sources  

SciTech Connect

High current short pulse ion beams can be generated by using a multicusp source. This is accomplished by switching the arc or the RF induction discharge on and off. An alternative approach is to maintain a continuous plasma discharge and extraction voltage but control the plasma flow into the extraction aperture by a combination of magnetic and electric fields. Short beam pulses can be obtained by using a fast electronic switch and a dc bias power supply. It is also demonstrated that very short beam pulses ({approximately}10{mu}s) with high repetition rate can be formed by a laser-driven LaB{sub 6} or barium photo-cathode. {copyright} {ital 1997 American Institute of Physics.}

Leung, K. [Lawrence Berkeley National Laboratory, University of California, Berkeley, California 94720 (United States)

1997-02-01

33

Several short analysis records and other communications concerning catalyst 10927  

Microsoft Academic Search

These reports are very short. One is a letter to Leuna mentioning their observation over several months of a gradual increase in ash content and possibly a lowering of catalyst activity of the catalyst furnished by Leuna. Another is a letter to Leuna, apparently responding to a warning from Leuna that the catalyst could catch fire during handling or transporting;

K. Wissel; F. Montfort; Fruhwirth

1941-01-01

34

10-Mbps Short-Range Baseband Wireless Communications via Quasi-Static Electric Fields  

NASA Astrophysics Data System (ADS)

We propose a novel short-range wireless communications technology that uses quasi-static electric fields; it enables data communication between devices separated by up to 10cm via dielectric media at a speed of 10Mbps. It is considered to be a secure wireless technology since communication area is restricted to below about 10cm. To suppress electromagnetic radiation, we adopted a baseband transmission scheme in which the quasi-static electric field is directly modulated by 10BASE-T data signals. Since the spectra of the data signals are concentrated to below 20MHz, the amplitude of the electric field rapidly decreases outside the communication area. This contributes to enhancing security of the communications system. In this paper, we explain a basic principle of the short-range wireless communications technology. Since baseband data signals are carried by the quasi-static electric field, the quality of the communication is easily degraded by the existence of the earth ground. To isolate the communications system from the earth ground, we introduce a novel electro-optic sensor to receive the quasi-static electric field. With the electro-optic sensor, stable data communication is possible at 10Mbps via dielectric materials, such as a wooden table.

Sasaki, Ai-Ichiro; Furuya, Akinori; Shinagawa, Mitsuru

35

Radiation characteristics of short backfire antenna applicable to mobile communications  

NASA Astrophysics Data System (ADS)

A numerical analysis of the short backfire antenna (SBA) is performed using the method of moments with the wire-grid model. The radiation characteristics of this antenna, including the radiation pattern and the antenna gain, are clarified. Comparisons with measured data were carried out, and good agreement was obtained. It is pointed out that the theoretical approach presented here can be used to optimize the performance characteristics of the SBF antenna.

Takeuchi, Kazunori; Shiokawa, Takayasu; Yasunaga, Masayuki

1991-10-01

36

Study on the Advanced MAC Scheduling Algorithm for the Infrared Dedicated Short Range Communication  

Microsoft Academic Search

\\u000a Dedicated Short Range Communication (IR-DSRC) is a communication system between Rode Side Equipment (RSE) and On Board Equipment\\u000a (OBE) in a vehicle. Wireless resources shared among nodes should be efficiently allocated in the telecommunication system,\\u000a and a MAC scheduling algorithm is needed. The purpose of the MAC scheduling algorithm is improving the efficiency after considering\\u000a the QoS requirements of each

Sujin Kwag; Sangsun Lee

2005-01-01

37

Short signalling distances make plant communication a soliloquy.  

PubMed

Plants respond to attack by herbivores or pathogens with the release of volatile organic compounds. Neighbouring plants can receive these volatiles and consecutively induce their own defence arsenal. This 'plant communication', however, appears counterintuitive when it benefits independent and genetically unrelated receivers, which may compete with the emitter. As a solution to this problem, a role for volatile compounds in within-plant signalling has been predicted. We used wild-type lima bean (Phaseolus lunatus) to quantify under field conditions the distances over which volatile signals move, and thereby determine whether these cues will mainly trigger resistance in other parts of the same plant or in independent plants. Independent receiver plants exhibited airborne resistance to herbivores or pathogens at maximum distances of 50 cm from a resistance-expressing emitter. In undisturbed clusters of lima bean, over 80 per cent of all leaves that were located around a single leaf at this distance were other leaves of the same plant, whereas this percentage dropped below 50 per cent at larger distances. Under natural conditions, resistance-inducing volatiles of lima bean move over distances at which most leaves that can receive the signal still belong to the same plant. PMID:20554558

Heil, Martin; Adame-Álvarez, Rosa M

2010-06-16

38

Short signalling distances make plant communication a soliloquy  

PubMed Central

Plants respond to attack by herbivores or pathogens with the release of volatile organic compounds. Neighbouring plants can receive these volatiles and consecutively induce their own defence arsenal. This ‘plant communication’, however, appears counterintuitive when it benefits independent and genetically unrelated receivers, which may compete with the emitter. As a solution to this problem, a role for volatile compounds in within-plant signalling has been predicted. We used wild-type lima bean (Phaseolus lunatus) to quantify under field conditions the distances over which volatile signals move, and thereby determine whether these cues will mainly trigger resistance in other parts of the same plant or in independent plants. Independent receiver plants exhibited airborne resistance to herbivores or pathogens at maximum distances of 50 cm from a resistance-expressing emitter. In undisturbed clusters of lima bean, over 80 per cent of all leaves that were located around a single leaf at this distance were other leaves of the same plant, whereas this percentage dropped below 50 per cent at larger distances. Under natural conditions, resistance-inducing volatiles of lima bean move over distances at which most leaves that can receive the signal still belong to the same plant.

Heil, Martin; Adame-Alvarez, Rosa M.

2010-01-01

39

Empirical Analysis on the Human Dynamics of a Large-Scale Short Message Communication System  

NASA Astrophysics Data System (ADS)

Research on human behavior has attracted increasing attention recently because of its scientific significance and potential applications. Some empirical results have indicated that the timing of many human activities follows non-Poisson statistics. We analyze a real-life huge dataset of short message communication with 6326713 users and 37577781 records during the 2006 Chinese New Year. The results show that the number of short message sendings, the interevent time between two consecutive short message sendings and the response time all follow heavy-tailed distribution. We further observe a strongly positive correlation between the activity and the power-law exponent of the interevent time distribution. In addition, the short message communication system displays a bursty property yet no memory effects, which is in particular different from some well-studied human-activited systems such as email-sending, library-loaning and file printing.

Zhao, Zhi-Dan; Xia, Hu; Shang, Ming-Sheng; Zhou, Tao

2011-06-01

40

Acoustic communication in two freshwater gobies: ambient noise and short-range propagation in shallow streams.  

PubMed

Noise is an important theoretical constraint on the evolution of signal form and sensory performance. In order to determine environmental constraints on the communication of two freshwater gobies Padogobius martensii and Gobius nigricans, numerous noise spectra were measured from quiet areas and ones adjacent to waterfalls and rapids in two shallow stony streams. Propagation of goby sounds and waterfall noise was also measured. A quiet window around 100 Hz is present in many noise spectra from noisy locations. The window lies between two noise sources, a low-frequency one attributed to turbulence, and a high-frequency one (200-500 Hz) attributed to bubble noise from water breaking the surface. Ambient noise from a waterfall (frequencies below 1 kHz) attenuates as much as 30 dB between 1 and 2 m, after which values are variable without further attenuation (i.e., buried in the noise floor). Similarly, courtship sounds of P. martensii attenuate as much as 30 dB between 5 and 50 cm. Since gobies are known to court in noisy as well as quiet locations in these streams, their acoustic communication system (sounds and auditory system) must be able to cope with short-range propagation dictated by shallow depths and ambient noise in noisy locations. PMID:12880062

Lugli, M; Fine, M L

2003-07-01

41

Short communication Potential of halophytes as source of edible oil  

Microsoft Academic Search

Seeds of Arthrocnemum indicum, Alhaji maurorum, Cressa cretica, Halopyrum mucronatum, Haloxylon stocksii and Suaeda fruticosa were analyzed to determine their potential to be used as source of edible oil. The quantity of oil present varied from 22% to 25%. The amounts of unsaturated fatty acids were high (65-74%) except in A. maurorum. The lipids in the seeds were found to

D. J. Weber; R. Ansari; B. Gul; M. Ajmal Khan

42

Short Communication: Pasteurization of Milk Abolishes Bovine Herpesvirus 4 Infectivity  

Microsoft Academic Search

Bovine herpesvirus 4 (BoHV-4) is a gammaherpesvi- rus highly prevalent in the cattle population that has been isolated from the milk and the serum of healthy infected cows. Several studies reported the sensitivity and the permissiveness of some human cells to BoHV-4 infection. Moreover, our recent study demonstrated that some human cells sensitive but not permissive to BoHV-4 support a

C. Bona; B. Dewals; L. Wiggers; K. Coudijzer; A. Vanderplasschen; L. Gillet

2005-01-01

43

Seed treatment with GA 3 or stratification enhances emergence of some strawberry tree genotypes - Short communication  

Microsoft Academic Search

Demirsoy L., Demirsoy H., Celikel G., Macit I., Ersoy B. , 2010: Seed treatment with GA 3 or stratification en - hances emergence of some strawberry tree genotypes - Short communication . Hort. Sci. (Prague), 37: 34-37. The strawberry tree is a valuable ornamental plant because of its attractive red fruits in the fall and winter, and pink - ish-white

L. Demirsoy; H. Demirsoy; G. Celikel; I. Macit; B. Ersoy

2010-01-01

44

Smart Card Applications and Mobility in a World of Short Distance Communication  

Microsoft Academic Search

Abstract The CASTING project is concerned with the application of smart card technology in combination with short distance wireless communication. This report focuses on secure access to Web pages, meaning that the right person has access to his or her personal Web pages in a manner that respects integrity, authenticity and confidentiality. This requires authentication of users, which is achieved

Michael Rohs; Harald Vogt

2001-01-01

45

Short communication: A comparative analysis of recombinant chymosins.  

PubMed

The first step in cheesemaking is the milk clotting process, in which ?-caseinolytic enzymes contribute to micelle precipitation. The best enzyme for this purpose is chymosin because of its high degree of specificity toward ?-casein. Although recombinant bovine chymosin is the most frequently used chymosin in the industry, new sources of recombinant chymosin, such as goat, camel, or buffalo, are now available. The present work represents a comparative study of 4 different recombinant chymosins (goat and buffalo chymosins expressed in Pichia pastoris, and bovine and camel chymosin expressed in Aspergillus niger). Recombinant goat chymosin exhibited the best catalytic efficiency compared with the buffalo, bovine, or camel recombinant enzymes. Moreover, recombinant goat chymosin exhibited the best specific proteolytic activity, a wider pH range of action, and a lower glycosylation degree than the other 3 enzymes. In conclusion, we propose that recombinant goat chymosin represents a serious alternative to recombinant bovine chymosin for use in the cheesemaking industry. PMID:22281325

Vallejo, J A; Ageitos, J M; Poza, M; Villa, T G

2012-02-01

46

Short communication: Reactivity of diacetyl with cleaning and sanitizing agents.  

PubMed

Diacetyl is used to impart a buttery flavor to numerous food products such as sour cream, cottage cheese, vegetable oil-based spreads, baked goods, and beverages. Recent studies have linked exposure to high concentrations of diacetyl and the onset of bronchiolitis obliterans. Due to the reported risks that diacetyl may pose, many food companies have altered practices to reduce worker exposure to diacetyl, including the use of personal respirators, improved air handling systems, and adequate cleaning practices. Commonly used cleaning and sanitizing agents may be reactive with diacetyl; however, the efficacy of these chemicals has not been studied in detail and remains unclear. The objective of this work was to study the reaction chemistry of diacetyl with common industrial cleaning and sanitizing chemicals. The reactions were assessed at equimolar concentrations and analyzed by gas chromatography-mass spectrometry. Peroxyacetic acid was most reactive with diacetyl (95% reduction in diacetyl), followed by sodium hypochlorite (76% reduction), and hydrogen peroxide (26% reduction). Benzalkonium chloride (BAC) did not react with diacetyl. Acetic acid was detected as the main product of reactions of diacetyl with peroxyacetic acid, sodium hypochlorite, and hydrogen peroxide. 1,1-Dichloro-2-propanone and 1,1,1-trichloropropanone were also identified as volatile reaction products in the sodium hypochlorite reactions. PMID:23063162

Rincon-Delgadillo, M I; Lopez-Hernandez, A; Rankin, S A

2012-10-11

47

Short communication  

Microsoft Academic Search

Papillomaviral dna has been identified in peripheral blood cells of both cattle and humans with and without associated disease and it has been suggested that such cells may act as sites of viral latency. In order to investigate the possibility of latent papillomaviral infection in the aetiopathogenesis of the equine sarcoid, peripheral blood derived DNA samples from 20 healthy and

L Nasir; S. T McFarlane; B. O Torrontegui; S. W. J Reid

1997-01-01

48

Efficient High Performance Collective Communication for Distributed Memory Environments  

ERIC Educational Resources Information Center

|Collective communication allows efficient communication and synchronization among a collection of processes, unlike point-to-point communication that only involves a pair of communicating processes. Achieving high performance for both kernels and full-scale applications running on a distributed memory system requires an efficient implementation…

Ali, Qasim

2009-01-01

49

Communication: Speaking and Listening; A Communication Skills Curriculum and Interdisciplinary Resource Guide for Junior High Schools.  

ERIC Educational Resources Information Center

|This five-unit junior high school speech communication curriculum guide is designed to provide seventh, eighth and ninth graders with an introductory course in speech-communication. Presupposing that communication or speech is a regularly scheduled subject in the junior high school, the outlined course requires at least one semester of academic…

Pearson, Eloise V., Ed.

50

An Energy-Harvesting Wireless-Interface SoC for Short-Range Data Communication  

Microsoft Academic Search

This paper describes design and verification of a wireless-interface SoC (system-on-a-chip) for a wireless battery-less mouse with short-range data-communication capability. The SoC comprises an RF transmitter and microcontroller. The SoC, which is powered by an electric generator that exploits gyration energy by dragging the mouse, was fabricated using a TSMC 0.18-um CMOS process. The features of the SoC are the

Shinji Mikami; Tetsuro Matsuno; Masayuki Miyama; Hiroshi Kawaguchi; Masahiko Yoshimoto; Hiroaki Ono

2006-01-01

51

Satellite Tactical Communications at High Latitudes.  

National Technical Information Service (NTIS)

Canada spans about 90 degrees of longitude and has requirements for tactical command and control communications as far north as to at least 84 degrees north latitude. These facts create unique problems when considering requirements for communication by sa...

K. L. Matheson

1983-01-01

52

High Average Power, High Energy Short Pulse Fiber Laser System  

SciTech Connect

Recently continuous wave fiber laser systems with output powers in excess of 500W with good beam quality have been demonstrated [1]. High energy, ultrafast, chirped pulsed fiber laser systems have achieved record output energies of 1mJ [2]. However, these high-energy systems have not been scaled beyond a few watts of average output power. Fiber laser systems are attractive for many applications because they offer the promise of high efficiency, compact, robust systems that are turn key. Applications such as cutting, drilling and materials processing, front end systems for high energy pulsed lasers (such as petawatts) and laser based sources of high spatial coherence, high flux x-rays all require high energy short pulses and two of the three of these applications also require high average power. The challenge in creating a high energy chirped pulse fiber laser system is to find a way to scale the output energy while avoiding nonlinear effects and maintaining good beam quality in the amplifier fiber. To this end, our 3-year LDRD program sought to demonstrate a high energy, high average power fiber laser system. This work included exploring designs of large mode area optical fiber amplifiers for high energy systems as well as understanding the issues associated chirped pulse amplification in optical fiber amplifier systems.

Messerly, M J

2007-11-13

53

Communicate!  

ERIC Educational Resources Information Center

|This ten chapter book is designed to provide high school students with an understanding of basic communication processes. The first five chapters include discussions of language development, function, and acquisition in relation to both human and non-human communication. The sixth chapter contains specimen linguistic analyses of speech and…

Chase, Stuart

54

Visible light communication in dynamic environment using image/high-speed communication hybrid sensor  

NASA Astrophysics Data System (ADS)

Visible Light Communication (VLC) is a wireless communication method using LEDs. LEDs can respond in high-speed and VLC uses this characteristics. In VLC researches, there are two types of receivers mainly, one is photodiode receiver and the other is high-speed camera. A photodiode receiver can communicate in high-speed and has high transmission rate because of its high-speed response. A high-speed camera can detect and track the transmitter easily because it is not necessary to move the camera. In this paper, we use a hybrid sensor designed for VLC which has advantages of both photodiode and high-speed camera, that is, high transmission rate and easy detecting of the transmitter. The light receiving section of the hybrid sensor consists of communication pixels and video pixels, which realizes the advantages. This hybrid sensor can communicate in static environment in previous research. However in dynamic environment, high-speed tracking of the transmitter is essential for communication. So, we realize the high-speed tracking of the transmitter by using the information of the communication pixels. Experimental results show the possibility of communication in dynamic environment.

Maeno, Keita; Panahpour Tehrani, Mehrdad; Fujii, Toshiaki; Okada, Hiraku; Yamazato, Takaya; Tanimoto, Masayuki; Yendo, Tomohiro

2012-01-01

55

High power short pulse fiber lasers  

Microsoft Academic Search

This paper describes characteristics of a short pulse doped rare earth fiber laser and amplifier. We have obtained very stable pico-second and femto-second laser pulses from fiber laser. An all-fiber laser and amplifier of a double-clad fiber are researched in detail. The pulse of 177fs at wavelength of ~1.50um has been got from fiber laser. The energy of single pulse

Guofu Chen; Wei Zhao; Yishan Wang; Guanglei Ding

2007-01-01

56

Applications of High Technology to Communication Instruction.  

ERIC Educational Resources Information Center

|Discusses classroom design and uses of interactive media. Covers the design of public speaking/interpersonal/small group communication classrooms, the simulation laboratory, the communication effectiveness trainer (ComET system), audience response systems, speech evaluation using computers, and system design considerations. (PD)|

Behnke, Ralph R.; O'Hair, H. Dan

1984-01-01

57

Experimental analysis of beamforming in high-speed railway communication  

Microsoft Academic Search

The demand of broadband high-mobility communication increased dramatically with the rapid development of high speed railway system. A beamforming platform through changing transmitter antenna direction base on real time receiver Global Positioning System (GPS) information was proposed to improve communication quality. Experiments were carried out over Taiwan High Speed Railway (THSR) train to analysis the tracking capability and path loss

Hung-Hsiang Wang; Hsin-An Hou

2011-01-01

58

622 Mbps High-speed satellite communication system for WINDS  

NASA Astrophysics Data System (ADS)

WINDS is the experimental communications satellite currently under joint development by Japanese Aerospace Exploration Agency (JAXA) and the National Institute of Information and Communications Technology (NICT). The high-speed satellite communication system is very effective for quick deployment of high-speed networks economically. The WINDS will realize ultra high-speed networking and demonstrate operability of satellite communication systems in high-speed internet. NICT is now developing high-speed satellite communication system for WINDS. High-speed TDMA burst modem with high performance TPC error correction is underdevelopment. Up to the DAC on the transmitter and from the ADC on the receiver, all modem functions are performed in the digital processing technology. Burst modem has been designed for a user data rate up to 1244 Mbps. NICT is developing the digital terminal as a user interface and a network controller for this earth station. High compatibility with the Internet will be provided.

Ogawa, Yasuo; Hashimoto, Yukio; Yoshimura, Naoko; Suzuki, Ryutaro; Gedney, Richard T.; Dollard, Mike

2006-07-01

59

Short communication: simultaneous analysis of reducing sugars and 5-hydroxymethyl-2-furaldehyde at a low concentration by high performance anion exchange chromatography with electrochemical detector, compared with HPLC with refractive index detector.  

PubMed

A simultaneous analysis of reducing sugars and 5-hydroxymethyl-2-furaldehyde of the Maillard reaction products was detailed. It was based on a high performance anion exchange chromatography with electrochemical detector system and an HPLC with refractive index detector. Results showed that high performance anion exchange chromatography with electrochemical detector using a CarboPac PA-1 column (Dionex Corp., Sunnyvale, CA) was more suitable for reducing sugars and 5-hydroxymethyl-2-furaldehyde determination, especially for trace analysis. The lowest detectable limit of reducing sugars and 5-hydroxymethyl-2-furaldehyde was 0.00005 mol/L in this experiment. However, HPLC with a refractive index detector always produces a tailing peak for 5-hydroxymethyl-2-furaldehyde, and mannose and fructose cannot be absolutely separated. The results of the present study could provide a more sensitive means for 5-hydroxymethyl-2-furaldehyde and reducing sugar detection. PMID:22959946

Guan, Y-G; Yu, P; Yu, S-J; Xu, X-B; Wu, X-L

2012-09-07

60

Short communication: Diurnal profiles of conjugated linoleic acids and trans fatty acids in ruminal fluid from cows fed a high concentrate diet supplemented with fish oil, linseed oil, or sunflower oil.  

PubMed

Trans-18:1 and 18:2 isomer composition in ruminal fluid during the daily feeding cycle was examined in 3 cows fed a high concentrate diet (35:65) with 5% (DM basis) sunflower oil (SO), 5% linseed oil (LO), or 2.5% fish oil (FO) in a 3 x 3 Latin square with 3 4-wk periods. Grass hay and concentrate mixtures were fed at 0900, 1300, and 1700 h daily. Ruminal fluid was collected at 0900, 1100, 1300, 1500, 1700, 2000, and 0000 h. Feeding SO resulted in the greatest mean concentrations (% of total fatty acids) of trans10,cis12-18:2 and cis9,trans11-18:2. In particular, trans10,cis12-18:2 with SO was greater at 1500 (0.29%), 2000 (0.34%), and 0000 h (0.25%) relative to 0900 h (0.07%). Cis9,trans11-18:2 concentration increased from 0.47% at 0900 h to a peak of 2.06% at 1100 h; it remained greater than the percentage determined at 0900 h at 1300 (1.4%) through 0000 h (1.1%). Concentration of trans11,cis15-18:2 was greatest with LO, ranging from 3.3% (0900 h) to a peak of 11.4% at 2000 h. Mean trans10-18:1 concentration ranked by diet was SO > FO > LO. Peak trans10-18:1 with SO was observed at 1700 h (14.9%) compared with 0900 h (5.1%). Trans11-18:1 did not differ with diet or time. Stearic acid decreased over time with all diets reaching minimum concentrations at 1700 to 2000 h relative to 0900 h. Feeding FO, however, decreased mean 18:0 concentration 4-fold compared with LO or SO. The moderate effect on concentration of trans-18:1 coupled with accumulation of 18:2 intermediates and the decrease of 18:0 over time suggest that oils reduced the biohydrogenation of 18:2 isomers to trans-18:1. PMID:15328270

Loor, J J; Ueda, K; Ferlay, A; Chilliard, Y; Doreau, M

2004-08-01

61

HIGH SCHOOL AGRICULTURAL COMMUNICATIONS COMPETENCIES: A NATIONAL DELPHI STUDY  

Microsoft Academic Search

The major purpose of this study was to identify competencies that should be achieved by high school students who complete courses in agricultural communications. Identification of the competencies came from industry leaders, high school agricultural education teachers, and university faculty in agricultural communications. A three-round Delphi technique was the principal procedure used to conduct the study with a total of

Cindy L. Akers; Paul R. Vaughn; Jacqui D. Haygood

62

TDX: A high-bandwidth crossbar-switched communication paradigm  

SciTech Connect

Digital signal processing systems under development today require scalable and reconfigurable high bandwidth communication resources between processing elements. Shared memory architectures require the ability to transfer data from one processor node to another, as well as maintaining data coherency such as provided by the Scalable Coherent Interface (SCI). Signal processing systems that must move large amounts of data between processor nodes, are best served by a communication system that allows reconfigurable streams of data to flow at deterministic rates with minimal overhead. A Time Domain Crossbar (TDX) communication system providing scalable, programmable, high-bandwidth, streaming communication has been developed and is described in this paper.

Pierce, P.E.; Eilers, D.L.; Schreiber, A.L.

1994-08-01

63

A Low-Cost Cooperative Strategy for Cellular Controlled Short-Range Communication Systems  

NASA Astrophysics Data System (ADS)

This letter is concerned with cellular controlled short-range communication (CCSRC) systems, which can provide a significant performance gain over the traditional cellular systems as shown in the literature. However, to obtain such a gain, CCSRC systems need perfect channel state information (CSI) of all users and the complexity of setting up the optimal cooperative clusters is factorial with respect to the number of potentially cooperative users, which is very unrealistic in practical systems. To solve this problem, we propose a novel cooperative strategy, where CCSRC systems only need the distances between all user pairs and the complexity of setting up the cooperative clusters is relatively low. Simulation results show that the performance of the proposed strategy is close to optimal.

Han, Han; Wang, Hao; Lin, Xiaokang

64

High capacity satellite communication system and key technologies  

Microsoft Academic Search

A high-capacity satellite communication system for Japan, with multiple beams and key technologies for onboard equipment, is described. The system will provide trunk transmission, digital business communication, and mobile communication. Advantages of the multibeam system include increased transmission capacity, reduction in earth-station antenna diameter, and frequency reuse. Onboard technologies discussed include cluster-feed horn design, reflector deployment, antenna pointing control (accurate

Y. Nagai; S. Okasaka; K. Nakagawa

1986-01-01

65

Communication.  

ERIC Educational Resources Information Center

|The following essays on communication are presented: communication as a condition of survival, communication for special purposes, the means of transmission of communication, communication within social and economic structures, the teaching of communication through the press, the teaching of modern languages, communication as a point of…

Strauss, Andre

66

The High Stakes of Risk Communication  

Microsoft Academic Search

Background.Risk communication involves coping with lack of public knowledge of science, scientific complexity and uncertainty, disagreement among experts on risk characterization and comparison, assumptions in risk assessment, the role of advocates, distortion in the mass media, manipulative public relations, and public outrage.Methods.This article summarizes two case studies, one of an emerging issue, the use of oxygenates in gasoline, and the

Ford Rowan

1996-01-01

67

Trend on High-speed Power Line Communication Technology  

NASA Astrophysics Data System (ADS)

High-speed power line communication (PLC) is useful technology to easily build the communication networks, because construction of new infrastructure is not necessary. In Europe and America, PLC has been used for broadband networks since the beginning of 21th century. In Japan, high-speed PLC was deregulated only indoor usage in 2006. Afterward it has been widely used for home area network, LAN in hotels and school buildings and so on. And recently, PLC is greatly concerned as communication technology for smart grid network. In this paper, the author surveys the high-speed PLC technology and its current status.

Ogawa, Osamu

68

High-data-rate ultrasonic through-metal communication.  

PubMed

A link-adaptive frequency division multiplexing (OFDM) ultrasonic physical layer is proposed for high-data-rate communications through metal walls. The ultrasonic link allows for communication without physical penetration of the metal barrier. Link-adaptive OFDM mitigates the severe frequency- selective fading of the ultrasonic channel and greatly improves throughput over impulse or narrowband communication systems. Throughput improvements of 300% are demonstrated over current narrowband low-frequency techniques, and show improved spectral efficiency over high-frequency techniques found in the literature. PMID:23007780

Wanuga, Kevin; Bielinski, Magda; Primerano, Richard; Kam, Moshe; Dandekar, Kapil R

2012-09-01

69

Short communication articles published in BJOMS during 2008–2009—an analysis of types of submission and subject material  

Microsoft Academic Search

The British Journal of Oral and Maxillofacial Surgery (BJOMS) accepts many types of papers that include leading articles, reviews, full length articles, and short communications. Many of the latter are isolated case reports of rare or interesting pathology, or personal experience of a difficult or unexpected complication. Case reports are considered to have a relatively low value in the advancement

P. A. Brennan; D. A. Mitchell; T. W. Walker; L. Cascarini; R. S. Oeppen

2010-01-01

70

Methods for UGV teleoperation with high latency communications  

NASA Astrophysics Data System (ADS)

In this project, we developed and demonstrated complementary UGV control methods for teleoperation with highlatency communications. The methods included latency protection, predictive displays, and supervisory control. Latency protection mitigate against typical types of high-latency teleoperation input errors. The Phase I latency protection methods included filtering the joysick commands, limiting the commanded rates as a function of latency, and emergency stop when the operator commands and OCU navigation video were out of phase. Predictive displays indicate to the operator the current state of the UGV, i.e., the state after all of the latent commands are executed (latent commands are those that have been issued but whose effects do not yet appear in the OCU display). We implemented two alternative predictive display methods: augmented reality using iconography to indicate the effects of the latent commands, and virtual reality which warps the image to show the view to reflect the latent commands. Supervisory control allows the operator to specify simple, short-range objectives that the UGV can accomplish on its own, without advanced sensing, path planning, etc. We implemented an effective "point-and-go" supervisory control system. We successfully implemented and demonstrated these methods on a Packbot© 510 EOD robot (made by iRobot Corporation), currently being used in-theater.

Witus, Gary; Hunt, Shawn; Janicki, Phil

2011-05-01

71

NHSE - National High Performance Computing and Communications (HPCC) Software Exchange  

NSDL National Science Digital Library

National Software Exchange for the High Performance Computing and Communications community has been established to facilitate the development and distribution of software enabling technologies for high performance computing a wide availability of high-quality, public-domain software for high performance computers. The exchange promotes software reuse and collaboration and information sharing between universities, research laboratories, and industry.

1997-01-01

72

Fiber Laser Front Ends for High Energy, Short Pulse Lasers  

SciTech Connect

We are developing a fiber laser system for short pulse (1-10ps), high energy ({approx}1kJ) glass laser systems. Fiber lasers are ideal for these systems as they are highly reliable and enable long term stable operation.

Dawson, J; Messerly, M; Phan, H; Siders, C; Beach, R; Barty, C

2007-06-21

73

Investigation of High Performance Short Fiber Reinforced Plastics.  

National Technical Information Service (NTIS)

Two short fiber systems, (Hercules' HM-S high modulus graphite and DuPont's PRD-49 high strength organic fiber, each in Fiberite's X-934 epoxide resin matrix) were studied to characterize their mechanical performance potential when compression molded to f...

J. L. Kardos M. J. Michno T. A. Duffy

1974-01-01

74

Soft calls and broadcast calls in the corncrake as adaptations to short and long range communication.  

PubMed

Because birds' acoustic signals function in antagonistic interactions between males and in female attraction, a majority of vocalisations are loud. In contrast, some birds, additionally produce soft vocalisations in escalated agonistic and sexual contexts. Nevertheless, the relationship between the acoustic parameters of such signals and their function is not clear. Here I investigate the sound transmission degradation properties of soft and broadcast (loud) calls in the corncrake using calls with natural and changed amplitude. I show that, if played at the same amplitude, the maximum limit for communication distance with soft calls was significantly shorter than that of broadcast calls, indicating that frequency structure is important in determining the range of both signals independently of their amplitude. At the same time, the values of excess attenuation were lower for soft calls than for broadcast calls at most distances, which suggests that the short transmission of soft calls is achieved mostly due to their low and narrow frequency ranges, promoting their masking by ambient noise. Finally, contrary to soft calls, changes in the energy of tails of echoes in broadcast calls were associated with the distance of propagation, which might be useful in assessing the distance to senders. I suggest that the acoustic structure of soft vocalisations can be used to limit the range of the signal, which might be helpful in eavesdropping avoidance, whereas broadcast calls are designed for long-range transmission. PMID:23876392

R?k, Pawe?

2013-07-19

75

A lower power reconfigurable multi-band transceiver for short-range communication  

NASA Astrophysics Data System (ADS)

A reconfigurable multi-mode multi-band transceiver for low power short-range wireless communication applications is presented. Its low intermediate frequency (IF) receiver with 3 MHz IF carrier frequency and the direct-conversion transmitter support reconfigurable signal bandwidths from 250 kHz to 2 MHz and support a highest data rate of 3 Mbps for MSK modulation. An integrated multi-band PLL frequency synthesizer is utilized to provide the quadrature LO signals from about 300 MHz to 1 GHz for the transceiver multi-band application. The transceiver has been implemented in a 0.18 ?m CMOS process. The measurement results at the maximum gain mode show that the receiver achieves a noise figure (NF) of 4.9/5.5 dB and an input 3rd order intermodulation point (IIP3) of -19.6/-18.2 dBm in 400/900 MHz band. The transmitter working in 400/900 MHz band can deliver 10.2/7.3 dBm power to a 50 ? load. The transceiver consumes 32.9/35.6 mW in receive mode and 47.4/50.1 mW in transmit mode in 400/900 MHz band, respectively.

Lingwei, Zhang; Baoyong, Chi; Nan, Qi; Liyuan, Liu; Hanjun, Jiang; Zhihua, Wang

2013-03-01

76

Underwater short range free space optical communication for a robotic swarm  

Microsoft Academic Search

Communication mechanism is a major design concern for a robotic swarm, as robots exchange data frequently in order to achieve a collective behavior. Communication using radio frequency (RF) is common if the swarm is land based, however, if the swarm operates underwater then a different form of communication mechanism is needed. In this paper, we discuss the implementation of a

Yu Fai Fung; Mingjun Dai; M. Fikret Ercan

2009-01-01

77

Adjunct payload for ISS high-rate communications  

NASA Astrophysics Data System (ADS)

An adjunct payload on commercial geosynchronous satellites is developed for ISS and similar high-rate communications. The technical parameters of this payload are set forth and bounds on user fees are established. Depending on the financial arrangements-e.g., development funds, long-term lease agreement, other value offered, commercial subscriptions-the adjunct payload can be a viable option for ISS communications service.

Mitchell, W. Carl; Cleave, Robert; Ford, David

1999-01-01

78

An Ethernet compatible low cost\\/high performance communication solution  

Microsoft Academic Search

The LAN-HUB is a new local area network designed to combine the properties of several existing LAN standards to provide highly reliable communication at a relatively lower cost per station, improve network capacity\\/delay performance and increase the LAN user's flexibility in configuring his network. The LAN-HUB network is configured around the CODEX 4320 LAN-HUB communication controllers which allow up to

Imrich Chlamtac; Alex Herman

1987-01-01

79

Spontaneous Radiation Emission from Short, High Field Strength Insertion Devices  

SciTech Connect

Since the earliest papers on undulaters were published, it has been known how to calculate the spontaneous emission spectrum from ''short'' undulaters when the magnetic field strength parameter is small compared to unity, or in ''single'' frequency sinusoidal undulaters where the magnetic field strength parameter is comparable to or larger than unity, but where the magnetic field amplitude is constant throughout the undulater. Fewer general results have been obtained in the case where the insertion device is both short, i.e., the magnetic field strength parameter changes appreciably throughout the insertion device, and the magnetic field strength is high enough that ponderomotive effects, radiation retardation, and harmonic generation are important physical phenomena. In this paper a general method is presented for calculating the radiation spectrum for short, high-field insertion devices. It is used to calculate the emission from some insertion device designs of recent interest.

Geoffrey Krafft

2005-09-15

80

Short communications published online in the British Journal of Oral and Maxillofacial Surgery during 2010-2011.  

PubMed

The British Journal of Oral and Maxillofacial Surgery (BJOMS) publishes many types of papers including original articles, review articles, and short communications. Many of the latter are isolated case reports of rare or interesting diseases or of difficult or unexpected complications. While case reports are sometimes considered to be of little educational or clinical value, and as such do little to advance medical knowledge, they do have an important role, and many trainees begin their publishing careers writing such papers. There is increasing pressure for space in paper medical journals and, for this reason, some journals either limit or do not publish short publications in print copy but instead put them online. Using established criteria, we previously evaluated all 142 short communications published in the BJOMS during 2008-2009 and found that 48% of them had little or no educational value. As a result, the editorial board of BJOMS took the decision to publish most short communications online only. We have now analysed 48 short communications that were published online only during 2010-2011. Most (80%) were single case reports that covered virtually the whole remit of the specialty, and over half (56%) were published by authors based in the UK. While many of these papers did not add important new information to existing knowledge, these types of article are clearly of value both for trainees and for experienced surgeons. We think that these should continue to be supported as, in addition to their educational value, they are an excellent way for trainees to start to write. PMID:22621907

Colbert, S; Southorn, B; Rosenbaum, G; Aldridge, T; Brennan, P A

2012-05-21

81

A Wireless-Interface SoC Powered by Energy Harvesting for Short-range Data Communication  

Microsoft Academic Search

This paper describes the design and estimation of a wireless-interface SoC for wireless battery-less mouse with short-range data communication capability. It comprises an RF transmitter and microcontroller. An SoC, which is powered by an electric generator that exploits gyration energy by dragging the mouse, was fabricated using the TSMC 0.18-mum CMOS process. Features of the SoC are the adoption of

S. Mikami; T. Matsuno; M. Miyama; M. Yoshimoto; H. Ono

2005-01-01

82

High bandwidth electro-optic technology for intersatellite optical communications  

NASA Astrophysics Data System (ADS)

The research and development of electronic and electro-optic components for geosynchronous and low earth orbiting satellite optical high bandwidth communications at the NASA-Goddard Space Flight Center is reviewed. Intersatellite optical communications retains a strong reliance on microwave circuit technology in several areas - the microwave to optical interface, the laser transmitter modulation driver and the optical receiver. A microwave to optical interface is described requiring high bandwidth electronic downconverters and demodulators. Electrical bandwidth and current drive requirements for the laser modulation driver for three laser alternatives are discussed. Bandwidth and noise requirements are presented for optical receiver architectures.

Krainak, Michael A.

1992-12-01

83

High Average Power, High Energy Short Pulse Fiber Laser System  

Microsoft Academic Search

Recently continuous wave fiber laser systems with output powers in excess of 500W with good beam quality have been demonstrated [1]. High energy, ultrafast, chirped pulsed fiber laser systems have achieved record output energies of 1mJ [2]. However, these high-energy systems have not been scaled beyond a few watts of average output power. Fiber laser systems are attractive for many

Messerly

2007-01-01

84

Multicultural Communication: Assessing, Facilitating, and Evaluating Competency-Based Oral Interactions. Short Course No. 6.  

ERIC Educational Resources Information Center

|This paper discusses assessing the oral communication skills of non-native speakers of English enrolled in pre-vocational programs at Golden West College (California), presents the locally developed assessment instrument, and discusses multicultural communication intervention strategies educators can use to empower students. The first part of the…

Flores, Norma Landa

85

The research of high efficient optical fiber coupling technology in space laser communication  

NASA Astrophysics Data System (ADS)

With the development of optical fiber communications, especially the maturity of the optical amplifiers and the WDM technology, space optical communication at 1550 nm becomes a promising solution for future high speed satellite communication. Receiving technology with optical amplifiers and coupling space light into single mode fiber are key technologies in space optical communication at 1550 nm. Free-space-to-fiber coupling technique investigated in this paper is the first challenge of applying fiber communication techniques to free space optical communications. We analyzed the factors that affect the efficiency of free-space-to single-mode-fiber coupling based on mode-matching theory of electromagnetic fields. On this objective, in this paper, the theoretical analysis of the effect of atmospheric turbulence on the space light-single mode fiber coupling efficiency is discussed. On this basis, the short-distance experiment coupling space light into single mode fiber is carried out. 1. The main factors affecting the process coupling space light into single mode fiber are analyzed. This paper introduced the statistical theory of atmospheric turbulence and gave out the main turbulence parameters and meteyard based on the theory of the space light-single mode fiber coupling efficiency under ideal conditions. 2. The influence of atmospheric turbulence on the space light-single mode fiber coupling efficiency is analyzed and simulated. In the weak turbulence condition, mathematical model of the mean coupling efficiency and its fluctuation variance was given. And the fluctuation variance of coupling efficiency was simulated studied under the atmospheric conditions. The influences on the average coupling efficiency was theoretically studied, which were induced by the structure constant of atmospheric refractive index, the diameter of coupling lens and the single-mode fiber mode field radius. 3. Validating the theoretical model by a experiment under a short link coupling condition. The results of this paper lay the theoretical and experimental foundation for indeed establishing the efficient space light-single mode fiber coupling systems.

Wang, Hao-zeng; Tong, Shou-feng; Zhang, Lei; Yang, Hong-kun

2013-08-01

86

A High Speed Interleaver for Emerging Wireless Communications  

Microsoft Academic Search

In this paper, a novel high-speed interleaver\\/deinterleaver is proposed. As data rates demanded in emerging communication applications increase, architectures for high-speed interleaving become essential. Three pipelined blocks comprise the interleaver to execute three permutation steps in high speed. The addition of static random access memories (SRAM) in stage 1 speeds up 24 times of interleaving efficiency. Operating at 200 MHz,

Yuan-Wei Wu; Pangan Ting; Hsi-Pin Ma

2005-01-01

87

The Interaction of High Density Short Pulse Laser with Matter  

NASA Astrophysics Data System (ADS)

The study of the interaction of High Density Short Pulse (HDSP) lasers with matter is an important rapidly expanding branch of Physics. Since 1985 these lasers have been developed to generate very short pulses with typical high performance parameters: peak powers up to hundreds of TW, pulse duration less than 20 fs, pulse energy more than 2J, repetition rate up to 10 Hz and wavelength of 800nm that could be lowered through higher harmonic generation. When such photons are properly focused on a target, creation of simultaneous unprecedented conditions in the laboratories within very short time takes place, namely: brightness up to 1020 W/cm2, electric fields up to 1011 V/cm, magnetic fields up to 109 gauss, temperatures of the order of 1012 °K, pressures ~109 bars and acceleration of up to 1026cm/s2. These conditions could definitely initiate severe nonlinearities within the exposed materials. The main objective of this paper is to review the studies on particle generation, particularly neutrons, by the interaction of high intensity lasers with solid or gas targets. Then propose their possible applications.

El Nadi, Lotfia; Omar, Magdy M.

2011-06-01

88

Reconfigurable signal processing ASIC architecture for high speed data communications  

Microsoft Academic Search

A flexible and reconfigurable signal processing ASIC architecture has been developed, simulated and synthesized. The proposed architecture can be used to realize any one of several functional blocks needed for the physical layer implementation of high speed data communication systems operating at symbol rates over 60 Msamples\\/sec. In fact, multiple instances of a chip based on this architecture each operating

Eugene Grayver; Babak Daneshrad

1998-01-01

89

3G HSPA for Broadband Communications with High Speed Vehicles  

Microsoft Academic Search

This paper presents a proof of concept for a continuous superior quality Broadband Vehicular communication system enabled through 3G HSPA in very high speed mobility scenarios (beyond 300 km\\/h), suitable for telemetry applications in trains, emergency vehicles and motor sport events. The system is quite unique as radio transmission for telemetry services under extreme speed conditions requires not only superior

Santiago Tenorio; Paul Spence; Beatriz Garriga; Javier Lopez; Aitor Garcia; Miguel Arranz

2010-01-01

90

Overlapped discrete multitone modulation for high speed copper wire communications  

Microsoft Academic Search

Multicarrier modulation possesses several properties which make it an attractive approach for high speed copper wire communication networks. Among these properties are the ability to efficiently access and distribute multiplexed data streams, and a reduced susceptibility to impulsive, as well as to narrowband channel disturbances. In digital implementations of multicarrier modulation, subcarrier generation and data modulation are accomplished digitally using

Stuart D. Sandberg; Michael A. Tzannes

1995-01-01

91

Overlapped Discrete Multitone Modulation for High Speed Copper Wire Communication  

Microsoft Academic Search

Multicarrier modulation possesses several properties which make it an attractive approach for high speed copper wire communications networks. Among these properties are the ability to efficiently access and distribute multiplexed data streams, and a reduced susceptibility to impulsive, as well as to narrowband channel disturbances. In digital implementations of multicarrier modulation, subcarrier generation and data modulation are accomplished digitally using

Stuart D. Sandberg; Michael A. Tzannes

1995-01-01

92

A secure communications infrastructure for high-performance distributed computing  

SciTech Connect

Applications that use high-speed networks to connect geographically distributed supercomputers, databases, and scientific instruments may operate over open networks and access valuable resources. Hence, they can require mechanisms for ensuring integrity and confidentially of communications and for authenticating both users and resources. Security solutions developed for traditional client-server applications do not provide direct support for the program structures, programming tools, and performance requirements encountered in these applications. The authors address these requirements via a security-enhanced version of the Nexus communication library; which they use to provide secure versions of parallel libraries and languages, including the Message Passing Interface. These tools permit a fine degree of control over what, where, and when security mechanisms are applied. In particular, a single application can mix secure and nonsecure communication, allowing the programmer to make fine-grained security/performance tradeoffs. The authors present performance results that quantify the performance of their infrastructure.

Foster, I.; Koenig, G.; Tuecke, S. [and others

1997-08-01

93

Communications.  

National Technical Information Service (NTIS)

Communication in its many forms is a critical component for an effective Space Grant Program. Good communication is needed within individual Space Grant College/Consortia, for example between consortium affiliates and the consortium program office. Effect...

D. D. Stouffer

1990-01-01

94

High-order harmonic generation with short-pulse lasers  

NASA Astrophysics Data System (ADS)

Recent progress in the understanding of high-order harmonic conversion from atoms and ions exposed to high-intensity, short-pulse optical lasers is reviewed. We find that ions can produce harmonics comparable in strength to those obtained from neutral atoms, and that the emission extends to much higher order. Simple scaling laws for the strength of the harmonic emission and the maximum observable harmonic are suggested. These results imply that the photoemission observed in recent experiments in helium and neon contains contributions from ions as well as neutrals.

Schafer, Kenneth J.; Krause, Jeffrey L.; Kulander, Kenneth C.

1993-07-01

95

System and method that suppresses intensity fluctuations for free space high-speed optical communication  

DOEpatents

A high-speed (Gbps), free space optical communication system is based on spectral encoding of radiation from a wide band light source, such as a laser. By using partially coherent laser beams in combination with a relatively slow photosensor, scintillations can be suppressed by orders of magnitude for distances of more than 10 km. To suppress the intensity fluctuations due to atmospheric turbulence, a source with partial transverse coherence in combination with slow response time photodetector is used. Information is encoded in the spectral domain of a wideband optical source by modulation of spectral amplitudes. A non-coherent light source with wide spectrum (an LED, for example) may be used for high-speed communication over short (less than about a mile) distances.

Berman, Gennady P. (Los Alamos, NM); Bishop, Alan R. (Los Alamos, NM); Nguyen, Dinh C. (Los Alamos, NM); Chernobrod, Boris M. (Santa Fe, NM); Gorshkov, Vacheslav N. (Kiev, UA)

2009-10-13

96

High incidence of SHOX anomalies in individuals with short stature  

PubMed Central

Objective To study the SHOX gene and the PAR1 region in individuals with short stature. Methods The study involved 56 cases of dyschondrosteosis and 84 cases of idiopathic short stature (ISS). The study was designed to determine the following: the prevalence of SHOX anomalies in ISS; the frequency of Madelung deformity in individuals with SHOX anomalies; and the value of a family history of short stature in deciding whether to test for the SHOX gene. Results 54 SHOX anomalies were observed, including 42 (68%) in the dyschondrosteosis group and 12 (15%) in the ISS group. The high frequency of SHOX anomalies in the ISS group can be explained by the large proportion of boys in this group, reflecting the difficulty in diagnosing dyschondrosteosis in young boys. Clinical evidence of Madelung deformity in six parents of ISS individuals emphasised the importance of family evaluation. Among the 54 SHOX anomalies, 33 PAR1 deletions were identified encompassing the SHOX gene (62%), one partial intragenic deletion (2%), nine deletions located downstream of the SHOX gene (16%), and 11 point mutations (20%). Conclusions These data emphasise the value of using microsatellite markers located within and downstream of the SHOX gene.

Huber, C; Rosilio, M; Munnich, A; Cormier-Daire, V

2006-01-01

97

Performance analysis of short-range NLOS UV communication system using Monte Carlo simulation based on measured channel parameters.  

PubMed

The research presented in this paper is a performance study of short-range NLOS ultraviolet (UV) communication system, using a Monte-Carlo-based system-level model, in which the channel parameters, such as the path loss and the background noise are experimentally measured using an outdoor UV communication test-bed. Various transceiver geometry and background noise condition are considered. Furthermore, 4 modulation schemes are compared, which provides an insight into the performance prediction and the system trade-offs among the path loss, the optical power, the distance, the link geometry, the bit rate and the bit error rate. Finally, advices are given on UV system design and performance improvement. PMID:23188312

Luo, Pengfei; Zhang, Min; Han, Dahai; Li, Qing

2012-10-01

98

High charge short electron bunches for wakefield accelerator structures development.  

SciTech Connect

The Argonne Wakefield Accelerator group develops accelerating structures based on dielectric loaded waveguides. We use high charge short electron bunches to excite wakefields in dielectric loaded structures, and a second (low charge) beam to probe the wakefields left behind by the drive beam. We report measurements of beam parameters and also initial results of the dielectric loaded accelerating structures. We have studied acceleration of the probe beam in these structures and we have also made measurements on the RF pulses that are generated by the drive beam. Single drive bunches, as well as multiple bunches separated by an integer number of RF periods have been used to generate the accelerating wakefields.

Conde, M. E.

1998-09-25

99

Analysis of High Power IGBT Short Circuit Failures  

SciTech Connect

The Next Linear Collider (NLC) accelerator proposal at SLAC requires a highly efficient and reliable, low cost, pulsed-power modulator to drive the klystrons. A solid-state induction modulator has been developed at SLAC to power the klystrons; this modulator uses commercial high voltage and high current Insulated Gate Bipolar Transistor (IGBT) modules. Testing of these IGBT modules under pulsed conditions was very successful; however, the IGBTs failed when tests were performed into a low inductance short circuit. The internal electrical connections of a commercial IGBT module have been analyzed to extract self and mutual partial inductances for the main current paths as well as for the gate structure. The IGBT module, together with the partial inductances, has been modeled using PSpice. Predictions for electrical paths that carry the highest current correlate with the sites of failed die under short circuit tests. A similar analysis has been carried out for a SLAC proposal for an IGBT module layout. This paper discusses the mathematical model of the IGBT module geometry and presents simulation results.

Pappas, G.

2005-02-11

100

High performance computing and communications: FY 1996 implementation plan  

SciTech Connect

The High Performance Computing and Communications (HPCC) Program was formally authorized by passage of the High Performance Computing Act of 1991, signed on December 9, 1991. Twelve federal agencies, in collaboration with scientists and managers from US industry, universities, and research laboratories, have developed the Program to meet the challenges of advancing computing and associated communications technologies and practices. This plan provides a detailed description of the agencies` HPCC implementation plans for FY 1995 and FY 1996. This Implementation Plan contains three additional sections. Section 3 provides an overview of the HPCC Program definition and organization. Section 4 contains a breakdown of the five major components of the HPCC Program, with an emphasis on the overall directions and milestones planned for each one. Section 5 provides a detailed look at HPCC Program activities within each agency.

NONE

1995-05-16

101

The softwater modem: a software modem for underwater acoustic communication: short paper  

Microsoft Academic Search

The Softwater Modem is a software modem for underwater acoustic communication that enables users to run applications on the familiar sockets interface without any additional hardware except for transducers and associated amplification. A standard TCP or UDP transport protocol runs on top of IP, which via the Linux TUN driver, runs on top of custom datalink and PHY layers tailored

Brian Borowski; Dan Duchamp

2009-01-01

102

RF\\/photonic antenna for high-capacity wireless communications  

Microsoft Academic Search

This paper proposes the integration of an antenna with a photodetector for high capacity wireless communications. The side-illuminated waveguide photodetector (WGPD) is used to convert the RF-modulated optical power into a microwave signal, which in turn is fed to an antenna. The WGPD is a standard p-i-n device grown on a semi-insulating InP substrate and fabricated using conventional techniques. The

Majid Khodier; Christos G. Christodoulou; George Tzeremes; Paul K. Yu

2002-01-01

103

A high-efficiency carrier estimator for OFDM communications  

Microsoft Academic Search

While multipath induced phase rotations can be dealt with by differential encoding in orthogonal frequency division multiplexing (OFDM) communications, the loss of orthogonality due to the carrier offset must be compensated before discrete Fourier transform (DFT)-based demodulation can be performed. In this letter, we present a high-performance\\/low-complexity blind carrier offset estimation algorithm by exploiting intrinsic structure information of OFDM signals.

Hui Liu; Ufuk Tureli

1998-01-01

104

Highly survivable communications: Complementary media packet switched networks  

NASA Astrophysics Data System (ADS)

The requirement for highly survivable communications (HSC) for essential command functions in military operations does not need any justification. The ability to communicate under extreme jamming levels and adverse propagation conditions, including high altitude nuclear events, is a very important requirement. There are also many natural disaster related requirements that also need such highly survivable communications. The prevalent and in a sense classical, approach to provide highly assured connectivity can be summarized as follows: Take a particular propagation medium and try to obtain the ultimate performance from it. There are many examples of this philosophy some successful, most not. Our approach, on the other hand, is to use complementary multi-media or mixed-media where communication links utilizing essentially commercial-off-the-shelf (COTS) equipment are integrated using packet radio (PR) techniques. There is also, in our view, an even more fundamental, recently discovered consideration why the expectation of continuous incremental refinement of a system using a given single media may be be achievable. This is derived from the theory of 'deterministic uncertainty' or more popularly known as 'theory of CHAOS', systems whose state space behavior has fractal characteristics. We will elaborate on this novel argument. Complementary multi-media approach has been the focus for all HSC communications activities at STC since 1982. The original STC studies and prototypes were in response to requirements of broadcasting (i.e., one-way transmission) information. A high frequency (HF)/meteorburst (MB) system was developed/prototyped/tested demonstrating the cost effectiveness of the approach. These results are reviewed. More recently, in 1992 STC has completed the development/test of an Open Systems Interconnection (OSI) HF packet radio protocol as no such open or non-proprietary protocol exists. This protocol has been fully tested, documented and made available to all NATO nations/industries. These extensive results show that significant improvements in throughput of up to many times are obtained. A similar development for an OSI MB protocol has also been completed and combined with the HF protocol to obtain an OSI HF/MB link layer protocol with unique properties for HSC networks. Description of these protocols and the relevant results are presented. highly survivable connectivity, by providing the most important ingredient of survivability, media diversity.

Yavuz, D.; Eken, F.; Karavassilis, N.

1994-07-01

105

Short distance intra coding scheme for high efficiency video coding.  

PubMed

This paper proposes a new intra coding scheme, known as short distance intra prediction (SDIP), for high efficiency video coding (HEVC) standardization work. The proposed method is based on the quadtree unit structure of HEVC. By splitting a coding unit into nonsquare units for coding and reconstruction, and therefore shortening the distances between the predicted and the reference samples, the accuracy of intra prediction can be improved when applying the directional prediction method. SDIP improves the intra prediction accuracy, especially for high-detailed regions. This approach is applied in both luma and chroma components. When integrated into the HEVC reference software, it shows up to a 12.8% bit rate reduction to sequences with rich textures. PMID:23060339

Cao, Xiaoran; Lai, Changcai; Wang, Yunfei; Liu, Lingzhi; Zheng, Jianhua; He, Yun

2012-10-05

106

Non-chemical and non-contact cell-to-cell communication: a short review  

PubMed Central

Cell-to-cell communication is the basis of coordinated cellular activity and thus fundamental for the functioning of biological systems. In a recently published research article by Chaban et al. (Am. J. Transl. Res., 5(1), 69-79), the authors report on interesting new experimental findings supporting a neuro-hormonal independent, non-diffusible cell-to-cell signaling. Our paper aims to (i) discuss some critical notions used by the authors to describe their findings, and (ii) briefly review related experimental work performed so far but not discussed in the original work of Chaban et al. In our opinion, the research on principles of non-chemical and non-contact cell-to-cell communication has the potential to offer new fundamental insights into biological processes. With this paper, we want to encourage future research on this topic by discussing critical issues and giving an overview of the current state of research.

Scholkmann, Felix; Fels, Daniel; Cifra, Michal

2013-01-01

107

Rad-Hard high speed serial communication using Honeywell SerDes macros  

Microsoft Academic Search

SerDes (serializer\\/deserializer) is a key component of serial communication architecture for high-speed servers and communications networking systems and point to point communication links. It is a vital building block for space-based high-speed data communications. Honeywell is enabling optimized communication systems with a SerDes macro-cell as part of their HX5000 rad-hard ASIC design platform and a SerDes standard part for next-generation

G. Roosevelt; D. Bueno; J. Haque; W. Roper; T. Romanko

2009-01-01

108

High speed intra-body communication for personal health care.  

PubMed

Intra-body communication (IBC) uses the conductive human body as the communication channel for data exchange. As the bio-sensor research is moving towards portable, wearable and implantable designs, IBC has significant potential applications for personal health care. Previous IBC research mainly focused on the electromagnetic (EM) IBC scheme, which resulted in low data rate (kbps). In this paper, we systematically studied the electric field (EF) IBC scheme, which enables 10Mbps data rate. The human body channel is thoroughly measured with attenuation, noise and distortion for the IBC application. High speed EF IBC links are tested with various modulation schemes. The minimum transmission power of different links is measured. PMID:19963724

Zhu, Hongjie; Xu, Ruoyu; Yuan, Jie

2009-01-01

109

Java-based communication in a High Performance Computing environment  

NASA Astrophysics Data System (ADS)

Java is one of the most widely used computer programming languages, however its use in High Performance Computing (HPC) is relatively low. A typical HPC environment consists of a number of multi-core computing nodes, while a typical application running in such an environment will normally contain CPU intensive code that can be executed in parallel. Such an application may require inter-node as well as intra-node communication. Message Passing Interface (MPI) is a language independent specification of an API to allow such communication. MPJExpress (Baker et al. 2006) and F-MPJ (Taboada et al. 2009) are Java-based implementations of MPI, designed with the efficient performance of data transfers as a main objective. In this paper we discuss the scalability of one approach of distributing data to compute nodes in HPC and we propose the design of an alternative data transfer system, building upon MPI.

Fries, A.; de Mora, J. Portell I.; Sirvent, R.

2011-02-01

110

Design constraints of high-bit-rate soliton communication systems  

NASA Astrophysics Data System (ADS)

We have examined the main constraints on the design of single-channel, high-capacity soliton communication systems. In the average soliton regime, the Gordon-Haus timing jitter limits the bit rate to less than 7 Gb/s for transoceanic fiber links, while for shorter transmission distances the main limitation is fiber perturbations arising from discrete in-line amplification. The use of dispersion-decreasing fibers and of periodic optical phase conjugation for jitter control can increase significantly the capacity of soliton communication systems. We found that the third-order dispersion assumes a prominent role in this case. Reducing this effect sufficiently, the main constraint becomes the soliton-soliton interactions and bit rates superior to 110 Gb/s can be achieved for amplifier spacings less than 80 km. For higher amplifier spacings the bit rate is limited by the Raman induced timing jitter.

Ferreira, Mario F.

1999-10-01

111

A new short-anoded IGBT with high emission efficiency  

NASA Astrophysics Data System (ADS)

A novel short-anoded insulated-gate bipolar transistor (SA-IGBT) with double emitters is proposed. At the on-state, the new structure shows extraordinarily high emission efficiency. Moreover, with a short-contacted anode, it further enhances the hole emission efficiency because of the crowding of the electrons. The forward voltage drop VF of this structure is 1.74 V at a current density 100 of A/cm2. Compared to the conventional NPT IGBT (1.94 V), segment-anode IGBT (SA-NPN 2.1 V), and conventional SA-IGBT (2.33 V), VF decreased by 10%, 17% and 30%, respectively. Furthermore, no NDR has been detected comparing to the SA-IGBT. At the off-state, there is a channel for extracting excessive carriers in the drift region. The turn-off loss Eoff of this proposed structure is 8.64 mJ/cm2. Compared to the conventional NPT IGBT (15.3 mJ/cm2), SA-NPN IGBT (12.8 mJ/cm2), and SA-IGBT (12.1 mJ/cm2), Eoff decreased by 43.7%, 32% and 28%, respectively.

Weizhong, Chen; Bo, Zhang; Zehong, Li; Min, Ren; Zhaoji, Li

2012-11-01

112

Closed-Loop Drilling System Using a High-Speed Communications Network.  

National Technical Information Service (NTIS)

A closed-loop downhole drilling system is disclosed that includes a high-speed communications network, comprising multiple nodes, integrated into a downhole drilling string. The high-speed communications network supports data transmission rates far exceed...

D. R. Hall

2004-01-01

113

Communication  

Microsoft Academic Search

\\u000a Communication impairment is a core deficit associated with autism spectrum disorder (ASD). Therefore, it should not be surprising\\u000a that this topic has become a major thrust of assessment and treatment in applied behavior analysis (ABA). The types of communication\\u000a skills to target for intervention and the behavioral assessment methods that can be used to identify these target behaviors\\u000a are reviewed

Jeff Sigafoos; Mark F. O’Reilly; Giulio E. Lancioni

114

Mobile Communication Implementation Techniques to Improve Last Mile High Speed FSO Communication  

Microsoft Academic Search

\\u000a As an affordable alternative solution for the current generation last mile wireless communication network access, the FSO\\u000a – Free Space Optical Communication has vast development in supporting of FSO communication. The primary advantages of FSO\\u000a system are the license free optical nodes, higher data rates, easy to install with less expensive setup. However, obtaining\\u000a the reliable communication link and higher

R. Srinivasan; A. Vijayaraj

115

HIGH-ENERGY EMISSION COMPONENTS IN THE SHORT GRB 090510  

SciTech Connect

We investigate the origin of the prompt and delayed emission observed in the short GRB 090510. We use the broadband data to test whether the most popular theoretical models for gamma-ray burst emission can accommodate the observations for this burst. We first attempt to explain the soft-to-hard spectral evolution associated with the delayed onset of a GeV tail with the hypothesis that the prompt burst and the high-energy tail both originate from a single process, namely, synchrotron emission from internal shocks (IS). Considerations on the compactness of the source imply that the high-energy tail should be produced in a late-emitted shell, characterized by a Lorentz factor greater than the one generating the prompt burst. However, in this hypothesis, the predicted evolution of the synchrotron peak frequency does not agree with the observed soft-to-hard evolution. Given the difficulties of a single-mechanism hypothesis, we test two alternative double-component scenarios. In the first, the prompt burst is explained as synchrotron radiation from IS and the high-energy emission (up to about 1 s following the trigger) as IS synchrotron-self-Compton. In the second scenario, in view of its long duration ({approx}100 s), the high-energy tail is decoupled from the prompt burst and has an external shock origin. In this case, we show that a reasonable choice of parameters does indeed exist to accommodate the optical-to-GeV data, provided the Lorentz factor of the shocked shell is sufficiently high. Finally, we attempt to explain the chromatic break observed around {approx}10{sup 3} s with a structured jet model. We find that this might be a viable explanation and that it lowers the high value of the burst energy derived by assuming isotropy, {approx}10{sup 53} erg, below {approx}10{sup 49} erg, which is more compatible with the energetics from a binary merger progenitor.

Corsi, Alessandra [Universita degli studi di Roma 'Sapienza' and INFN-Sezione di Roma, Piazzale Aldo Moro 2, 00185 Roma (Italy); Guetta, Dafne [INAF - Osservatorio Astronomico di Roma, Via Frascati 33, 00040 Monte Porzio Catone (Italy); Piro, Luigi, E-mail: alessandra.corsi@roma1.infn.i, E-mail: luigi.piro@iasf-roma.inaf.i, E-mail: guetta@oa-roma.inaf.i, E-mail: corsi@caltech.ed [INAF - Istituto di Astrofisica Spaziale e Fisica Cosmica di Roma, Via Fosso del Cavaliere 100, 00133 Roma (Italy)

2010-09-10

116

Research with high-power short-wavelength lasers  

SciTech Connect

Three important high-temperature, high-density experiments were conducted recently using the 10-TW, short-wavelength Novette laser system at the Lawrence Livermore National Laboratory. These experiments demonstrated successful solutions to problems that arose during previous experiments with long wavelength lasers (lambda greater than or equal to 1..mu..m) in which inertial confinement fusion (ICF), x-ray laser, and other high-temperature physics concepts were being tested. The demonstrations were: (1) large-scale plasmas (typical dimensions of up to 1000 laser wavelengths) were produced in which potentially deleterious laser-plasma instabilities were collisionally damped. (2) Deuterium-tritium fuel was imploded to a density of 20 g/cm/sup 3/ and a pressure of 10/sup 10/ atm. (3) A 700-fold amplification of soft x rays by stimulated emission at 206 and 209 A (62 eV) from Se/sup +24/ ions was observed in a laser-generated plasma. Isoelectronic scaling to 155 A (87 eV) in Y/sup +29/ was also demonstrated.

Holzrichter, J.F.; Campbell, E.M.; Lindl, J.D.; Storm, E.

1985-03-05

117

High performance germanium-on-silicon detectors for optical communications  

NASA Astrophysics Data System (ADS)

We demonstrate fast and efficient germanium-on-silicon p-i-n photodetectors for optical communications, with responsivities as high as 0.89 and 0.75 A/W at 1.3 and 1.55 mum, respectively, time response <200 ps and dark currents as low as 1.2 muA. Ge was epitaxially grown on Si by chemical vapor deposition, employing a low temperature buffer and cyclic thermal annealing to reduce the dislocation density. The overall performance is well suited for >2.5 Gb/s integrated receivers for the second and third fiber spectral windows.

Fama, Silvia; Colace, Lorenzo; Masini, Gianlorenzo; Assanto, Gaetano; Luan, Hsin-Chiao

2002-07-01

118

The Multi-Ring Topology - High-Performance Group Communication in Peer-to-Peer Networks  

Microsoft Academic Search

Emerging peer-to-peer applications require efficient group communication. However, current techniques for group communication are not optimal for peer-to-peer networks, which do not have group communication methods themselves. This paper presents the novel multi- ring topology, which is designed to meet requirements of high performance group communication in peer-to-peer networks. It improves data communication by applying several concepts: building overlay networks

Markus Junginger; Yugyung Lee

2002-01-01

119

Communication: An exact short-time solver for the time-dependent Schr?dinger equation  

PubMed Central

The short-time integrator for propagating the time-dependent Schrödinger equation, which is exact to machine’s round off accuracy when the Hamiltonian of the system is time-independent, was applied to solve dynamics processes. This integrator has the old Cayley’s form [i.e., the Padé (1,1) approximation], but is implemented in a spectrally transformed Hamiltonian which was first introduced by Chen and Guo. Two examples are presented for illustration, including calculations of the collision energy-dependent probability passing over a barrier, and interaction process between pulse laser and the I2 diatomic molecule.

Sun, Zhigang; Yang, Weitao

2011-01-01

120

A high current, short pulse electron source for wakefield accelerators  

SciTech Connect

Design studies for the generation of a high current, short pulse electron source for the Argonne Wakefield Accelerator are presented. An L-band laser photocathode rf gun cavity is designed using the computer code URMEL to maximize the electric field on the cathode surface for fixed frequency and rf input power. A new technique using a curved incoming laser wavefront to minimize the space charge effect near the photocathode is studied. A preaccelerator with large iris to minimize wakefield effects is used to boost the drive beam to a useful energy of around 20 MeV for wakefield acceleration experiments. Focusing in the photocathode gun and the preaccelerator is accomplished with solenoids. Beam dynamics simulations throughout the preaccelerator are performed using particle simulation codes TBCI-SF and PARMELA. An example providing a useful set of operation parameters for the Argonne Wakefield Accelerator is given. The effects of the sagitta of the curved beam and laser amplitude and timing jitter effects are discussed. Measurement results of low rf power level bench tests and a high power test for the gun cavity are presented and discussed.

Ho, Ching-Hung.

1992-01-01

121

A high current, short pulse electron source for wakefield accelerators  

SciTech Connect

Design studies for the generation of a high current, short pulse electron source for the Argonne Wakefield Accelerator are presented. An L-band laser photocathode rf gun cavity is designed using the computer code URMEL to maximize the electric field on the cathode surface for fixed frequency and rf input power. A new technique using a curved incoming laser wavefront to minimize the space charge effect near the photocathode is studied. A preaccelerator with large iris to minimize wakefield effects is used to boost the drive beam to a useful energy of around 20 MeV for wakefield acceleration experiments. Focusing in the photocathode gun and the preaccelerator is accomplished with solenoids. Beam dynamics simulations throughout the preaccelerator are performed using particle simulation codes TBCI-SF and PARMELA. An example providing a useful set of operation parameters for the Argonne Wakefield Accelerator is given. The effects of the sagitta of the curved beam and laser amplitude and timing jitter effects are discussed. Measurement results of low rf power level bench tests and a high power test for the gun cavity are presented and discussed.

Ho, Ching-Hung

1992-12-31

122

High incidence of SHOX anomalies in individuals with short stature  

Microsoft Academic Search

Objective: To study the SHOX gene and the PAR1 region in individuals with short stature.Methods: The study involved 56 cases of dyschondrosteosis and 84 cases of idiopathic short stature (ISS). The study was designed to determine the following: the prevalence of SHOX anomalies in ISS; the frequency of Madelung deformity in individuals with SHOX anomalies; and the value of a

C Huber; M Rosilio; A Munnich; V Cormier-Daire

2006-01-01

123

High performance MPI2 one-sided communication over InfiniBand  

Microsoft Academic Search

Many existing MPI-2 one-sided communication imple- mentations are built on top of MPI send\\/receive operations. Although this approach can achieve good portability, it suf- fers from high communication overhead and dependency on remote process for communication progress. To address these problems, we propose a high performance MPI-2 one- sided communication design over the InfiniBand Architec- ture. In our design, MPI-2

Weihang Jiang; Jiuxing Liu; Hyun-wook Jin; Dhabaleswar K. Panda; William Groppl; Rajeev Thakurt

2004-01-01

124

Hyperglue: Designing High-Level Agent Communication for Distributed Applications  

Microsoft Academic Search

We1 are building a new communication model and discov- ery system which will allow agent-based intelligent spaces to interact with one another. This new infrastructure layer, called Hyperglue, coordinates agent actions at a higher level than most agent communication does, providing an interface for communication at the level of \\

Stephen Peters; Gary Look; Kevin Quigley; Howard Shrobe; Krzysztof Gajos

2003-01-01

125

Armi: a High Level Communication Library for Stapl  

Microsoft Academic Search

ARMI is a communication library that provides a framework for expressing flne- grain parallelism and mapping it to a particular machine using shared-memory and message passing library calls. The library is an advanced implementation of the RMI protocol and handles low-level details such as scheduling incoming communication and aggregating outgoing communication to coarsen parallelism. These details can be tuned for

Nathan Thomas; Steven Saunders; Timmie G. Smith; Gabriel Tanase; Lawrence Rauchwerger

2006-01-01

126

Wireless communication employing high altitude long endurance aeronautical platforms  

Microsoft Academic Search

This article presents a possible alternative solution for wireless service providers. Wireless communication is currently the fastest developing branch in telecommunications. The number of wireless, especially mobile, subscribers is increasing at a much faster rate than the number of wire subscribers. Today, wireless communication is divided into terrestrial and satellite communications, both of which bring with it certain benefits and

S. Tomazic; A. Vugrinec; P. Skraba

2000-01-01

127

FIBREOPTIC DATA COMMUNICATION: Superdense wavelength-division multiplexing in high-bit-rate multichannel fibreoptic communication links  

NASA Astrophysics Data System (ADS)

A new flat-top format for highly spectrally efficient fibreoptic data communication links is studied. Analytic expressions are obtained for the averaged power spectrum of an optical signal and a strong dependence of the power spectrum shape on the frequency shift of an optical filter with respect to the centre of a specified channel is demonstrated. A direct numerical simulation of multichannel optical communication links based on this format is performed.

Shapiro, Elena G.; Fedoruk, Mikhail P.; Zakharyuta, M. V.

2006-06-01

128

High energy K-? radiography using high-energy, high-intensity, short-pulse lasers  

NASA Astrophysics Data System (ADS)

Many laser facilities utilizes x-ray backlighters to radiographically diagnose various stages of hydrodynamics experiments. These backlighters have x-ray energies <˜9 keV generated by thermal plasmas from long-pulse lasers. However, many future high energy density experiments on new facilities such as Omega-EP and NIF will perform experiments that will require backlighters in the 15-100 keV range and better than ˜10 ?m spatial resolution. High-energy K-? x-ray sources can be created through the interaction of high-energy electrons, generated by high-intensity short-pulse lasers, with target material. Not only K-? sources are more efficient way to generate high-energy photons but also advantageous in creating quasi-monochromatic backlighters by K-edge filters to provide required contrast. We have performed several experiments using the JanUSP, Vulcan 100 TW and Petawatt lasers to understand the K-? source characteristics and to implement a workable radiography. Our measurements show that the K-? size from a simple foil target is larger than 60 ?m thus less than optimally efficient as a point source for high-resolution imaging. We also measured the total K-? yield is invariant to the target thickness verifying that refluxing plays a major role in photon yields and that smaller radiating volumes emit brighter K-? radiation [1]. Thus, 1-D radiography with the required brightness and spatial resolution can be obtained using small-edge-on foils. Subsequently, we employed this technique to perform an EOS experiment in a 400 ?m thick Al sample. We tested many small volume sources in different geometrical shapes such as cone/wire and embedded wires to understand photon yields from these 2-D point sources. We will compare our measurements with hybrid-PIC LSP simulations. In addition, we are developing imaging detectors and diagnostics tools that are workable in the 15-100keV range. This paper will present the results. [1] H. S. Park et al., Rev. Sci. Instrum. 75, 4048 (2004)

Park, Hye-Sook

2005-10-01

129

Short-Length Raptor Codes for Free-Space Optical Communications  

Microsoft Academic Search

Free-space optical (FSO) links are competitive wireless links offering high data rate,security and low system complexity. Compared to radio-frequency (RF) links, FSOlinks offer high rates at gigabit-per-second (Gbps) level and relatively low cost. However, atmospheric scintillation and misalignment between optical transmitter and receiver impair data rates of FSO links. Scintillation and misalignment are slow fadingprocesses with a fading interval of

Wenzhe Zhang

2009-01-01

130

Short communication: immediate and deferred milk production responses to concentrate supplements in cows grazing fresh pasture.  

PubMed

The objective of this study was to determine the increase in milk production from supplementation that occurred after supplementation ceased. This portion of the total response (i.e., the deferred response), although accepted, is generally not accounted for in short-term component research projects, but it is important in determining the economic impact of supplementary feeding. Fifty-nine multiparous Holstein-Friesian dairy cows were offered a generous allowance of spring pasture [>45 kg of dry matter (DM)/cow per day) and were supplemented with 0, 3, or 6 kg (DM)/d of pelleted concentrate (half of the allowance at each milking event) in a complete randomized design. Treatments were imposed for the first 12 wk of lactation. Treatments were balanced for cow age (5.4 ± 1.68 yr), calving date (July 27 ± 26.0 d), and genetic merit for milk component yield. During the period of supplementation, milk yield and the yield of milk components increased (1.19 kg of milk, 0.032 kg of fat, 0.048 kg of protein, and 0.058 kg of lactose/kg of concentrate DM consumed), but neither body condition score nor body weight was affected. After concentrate supplementation ceased and cows returned to a common diet of fresh pasture, milk and milk component yields remained greater for 3 wk in the cows previously supplemented. During this 3-wk period, cows that previously received 3 and 6 kg of concentrate DM per day produced an additional 2.3 and 4.5 kg of milk/d, 0.10 and 0.14 kg of fat/d, 0.10 and 0.14 kg of protein/d, and 0.10 and 0.19 kg of lactose/d, respectively, relative to unsupplemented cows. This is equivalent to an additional 0.19 kg of milk, 0.006 kg of fat, 0.006 kg of protein, and 0.008 kg of lactose per 1 kg of concentrate DM previously consumed, which would not be accounted for in the immediate response. As a result of this deferred response to supplements, the total milk production benefit to concentrate supplements is between 7% (lactose yield) and 32% (fat yield) greater than the marginal response measured during the component experiment. Recommendations to dairy producers based on component feeding studies must be revised to include this deferred response. PMID:23375970

Roche, J R; Kay, J K; Rius, A G; Grala, T M; Sheahan, A J; White, H M; Phyn, C V C

2013-01-30

131

Short communication: Bacillus cereus capable of degrading SDS shows growth with a variety of detergents  

Microsoft Academic Search

A strain of Bacillus cereus was isolated from a detergent-polluted pond. This strain showed growth with exceedingly high concentration of both anionic and non-ionic detergents. Detergent such as SDS was rapidly taken up by the cells and degraded to dodecan-1-ol by the enzyme alkylsulphatase.

Kusum Lata Singh; Arvind Kumar; Ashok Kumar

1998-01-01

132

Short Communication: Effects of X-Rays on Growth and Germinal Tissue of Calves1  

Microsoft Academic Search

A study was carried out to measure the growth and germinal tissue responses of young bull calf whose testi- cles were exposed to different levels of high energy, pulsed beams (X rays). Treatments (absorbed doses) were 0, 1530, 1980, 3060, or 6300 rads. Body weights were measured monthly for 10 mo; testosterone concen- trations were measured in mo 2 and

R. L. Belyea; R. D. Curry; G. A. Mesyats; A. L. Filatov; T. E. Clevenger; M. A. Miller; R. S. Youngquist

2001-01-01

133

An Assessment Study of the Communication Reticence of High School Students.  

ERIC Educational Resources Information Center

A study was conducted to examine the communication reticence of high school students enrolled in required speech and writing courses. Approximately 200 students completed the Personal Report of Communication Apprehension (PRCA), the Unwillingness-to-Communicate Scale (UCS), and the Writing Apprehension Test (WAT). Data were then analyzed to…

McDowell, Earl E.

134

High speed 4×12.5Gbps WDM optical wireless communication systems for indoor applications  

Microsoft Academic Search

A novel high-speed optical wireless communication system incorporating WDM technology for indoor personal area networking applications is proposed and demonstrated. A 4×12.5Gbps mobile communication link is successfully demonstrated with error-free reception. OCIS codes: (060.2360) Fiber optics links and subsystems; (060.2605) Free-space optical communication.

Ke Wang; Ampalavanapillai Nirmalathas; Christina Lim; Efstratios Skafidas

2011-01-01

135

Short communication Toward increased utility of mtDNA in forensic identifications  

Microsoft Academic Search

The utility of mtDNA in forensic identifications is limited by its low power of discrimination and the absence of high quality mtDNA databases. Single nucleotide polymorphisms (SNPs) in the control region outside of hypervariable regions I and II (HVI\\/ HVII), and in the coding region of the mtDNA genome, can provide additional discrimination in mtDNA testing. We have identified particularly

Rebecca S. Just; Jodi A. Irwin; Jennifer E. O'Callaghan; Jessica L. Saunier; Michael D. Coble; Peter M. Vallone; John M. Butler; Suzanne M. Barritta; Thomas J. Parsons

136

Ka-band High-speed Communication Systems on Small Satellites for Future Advanced Communication Networks and Earth Observations  

NASA Astrophysics Data System (ADS)

The goal of this paper is to describe the capabilities and application methods of Ka-band communication systems for small satellites indicating contributions to future advanced communication networks and Earth observations. This study is based on the actual experience on the design of the Ka-band high-speed communication system of the small satellite Flying Laptop, which is developed at the Institute of Space Systems of the Universität Stuttgart. The objectives of the Ka-band communication system is to demonstrate high-speed communications with a data rate of up to 500 Mbit/s as well as to conduct scientific Earth observations. Flying Laptop satellite is also equipped with a Ku-band signal transmitter. The attenuation of the two transmission signals in Ka-/Ku-bands are measured with ground stations to estimate the local precipitation rate. The mathematical background and operational scenario of this measurement is summarized. The received Ka-band transmission signal is measured in different meteorological conditions to identify attenuation characteristics of the Ka-band signal due to rain, clouds, trace gases and so forth, which is of great interest for utilization of Ka-band frequencies for future broadband communications.

Kuwahara, Toshinori; Lengowski, Michael; Beyermann, Ulrich; Uryu, Alexander; Roeser, Hans-Peter

137

Visible light road-to-vehicle communication using high-speed camera  

Microsoft Academic Search

We have been proposing visible light road-to-vehicle communication at intersection, using LED traffic light as the transmitter and on-vehicle high-speed camera as the receiver. Visible light communication is a wireless communication method using luminance, transmitting data by emitting light. Thus when we use image sensor as the receiver, detection of the transmitter is required to enable the communication. In this

Shinya Iwasaki; Chinthaka Premachandra; Tomohiro Endo; Toshiaki Fujii; Masayuki Tanimoto; Yoshikatsu Kimura

2008-01-01

138

PM: An Operating System Coordinated High Performance Communication Library  

Microsoft Academic Search

. We have developed a new communication library, called PM,for the Myrinet gigabit LAN card, that has a dedicated processor andon-board memory to handle a communication protocol. In order to obtainhigh performance communication and support a multi-user environment,we have co-desgined PM, an operating system realized by adaemon process, and the run-time routine for a programming language.Several unique features, e.g., network

Hiroshi Tezuka; Atsushi Hori; Yutaka Ishikawa; Mitsuhisa Sato

1997-01-01

139

High performance computing and communications: Investment in American competitiveness  

NASA Astrophysics Data System (ADS)

This report presents the results of a study performed by Gartner Group, Inc. for the U.S. Department of Energy (DOE), through a contract with the Los Alamos National Laboratory (LANL). The purpose of the study is to estimate the economic impact of the Federal High Performance Computing and Communications (HPCC) Program which was proposed by the Office of Science and Technology Policy (OSTP), Executive Office of the President, on September 8, 1989. That Program is an implementation of the Research and Development Strategy for High Performance Computing, which was transmitted to Congress by OSTP on November 20, 1988. The objective of this Gartner Group study to provide an assessment of the likely economic impact and benefits of the Federal HPCC Program and the risks of non-support of this program. The goals of the HPCC Program are to: support computational advances through R and D effort; Reduce uncertainties to industry through increased cooperation and continued use of government as a market for High Performance Computing (HPC) prototypes; Support underlying research, network, and computational infrastructures; and support the U.S. human resource base.

1991-03-01

140

Communication Style and Cultural Features in High\\/Low Context Communication Cultures: A Case Study of Finland, Japan and India  

Microsoft Academic Search

People from different countries communicate in ways that often lead to misunderstandings. Our argument, based on Hall's theory of high\\/low context cul- tures (1959, 1966, 1976, 1983), is that these differences are related to different commu- nication cultures. We argue that Japan and Finland belong to high context cultures, while India is closer to a low context culture with certain

Shoji Nishimura; Anne Nevgi; Seppo Tell

141

High frequency sound attenuation in short flow ducts  

Microsoft Academic Search

A geometrical acoustics approach is proposed as a practical design tool for absorbent liners in such short flow ducts as may be found in turbofan engine nacelles. As an example, a detailed methodology is presented for three different types of sources in a parallel plate duct containing uniform ambient flow. A plane wave whose wavefronts are not normal to the

J. W. Posey

1978-01-01

142

Short Term Effects of Highly and Mildly Aggressive Video Games  

Microsoft Academic Search

Two experiments were conducted to examine the effects of playing different types of video games on players' short-term affective states. In the first experiment, college student subjects played 11 different video games and rated them on a number of characteristics. From these ratings, two games were selectedfor use in Experiment 2. These games differed only in the level of aggression

Craig A. Anderson; Catherine M. Ford

143

Stagings: Short Scripts for Middle and High School Students.  

ERIC Educational Resources Information Center

|Introducing students to the magic of theater and helping them develop dramatic skills, this book presents nine reproducible scripts for short plays (15 to 25 minutes) with characters and story lines that will appeal to young people. The scripts in the book encompass a variety of story types, from adaptations of well-known fairy tales to original…

Garner, Joan

144

Feasibility study to objectively assess activity and location of Hispanic preschoolers: a short communication.  

PubMed

Both physical and social environmental factors influence young children's physical activity, yet little is known about where Hispanic children are more likely to be active. We assessed the feasibility of simultaneously measuring, then processing objective measures of location and physical activity among Hispanic preschool children. Preschool-aged Hispanic children (n = 15) simultaneously wore QStarz BT100X global positioning system (GPS) data loggers and Actigraph GT3X accelerometers for a 24- to 36-hour period, during which time their parents completed a location and travel diary. Data were aggregated to the minute and processed using the personal activity location measurement system (PALMS). Children successfully wore the GPS data loggers and accelerometers simultaneously, 12 of which yielded data that met quality standards. The average percent correspondence between GPS- and diary-based estimates of types of location was high and Kappa statistics were moderate to excellent, ranging from 0.49-0.99. The between-method (GPS monitor, parent-reported diary) correlations of estimated participant-aggregated minutes spent on vehicle-based trips were strong. The simultaneous use of GPS and accelerometers to assess Hispanic preschool children's location and physical activity is feasible. This methodology has the potential to provide more precise findings to inform environmental interventions and policy changes to promote physical activity among Hispanic preschool children. PMID:23733298

O'Connor, Teresia M; Cerin, Ester; Robles, Jessica; Lee, Rebecca E; Kerr, Jacqueline; Butte, Nancy; Mendoza, Jason A; Thompson, Deborah; Baranowski, Tom

2013-05-01

145

Short communication: Occurrence of aflatoxin M1 in the Manchego cheese supply chain.  

PubMed

The importance of ewe milk lies in the production of high quality cheeses, such as Manchego cheese with a Protected Designation of Origin, whose safety must be guaranteed. In a 2-yr study, 407 bulk tank milk samples from farms and 82 silo milk and curd samples from cheese factories were collected from southeast Spain and tested for aflatoxin M1 (AFM1) using 2 commercial ELISA tests. Of these, 99.3% of the bulk tank samples had AFM1 levels below the European Union (EU) legal limit for milk (50 ng/kg), and well below the limit adopted by the Codex Alimentarius (500 ng/kg). Moreover, 98.8% of the silo milk and curd samples from cheese factories had AFM1 levels below the EU limit for milk. When considering median AFM1 concentrations, an average 4-fold increase was found in the final curd in relation to the corresponding silo milk. Control of AFM1 in Manchega ewe milk would enhance dairy product safety by the possible detection of faults in the manufacture of Manchego cheese. PMID:21605747

Rubio, R; Licón, C C; Berruga, M I; Molina, M P; Molina, A

2011-06-01

146

Short communication: rapid detection of milk fat adulteration with vegetable oil by fluorescence spectroscopy.  

PubMed

This study assessed the potential application of fluorescence spectroscopy in detecting adulteration of milk fat with vegetable oil and characterizing the samples according to the source of the fat. Pure butterfat was adulterated with different vegetable oils at various concentrations (0, 5, 10, 15, 20, 30, and 40%). Nonfat and reduced-fat milk were also adulterated with vegetable oils to simulate full-fat milk (3.2%). The 2- and 3-dimensional front-face fluorescence spectroscopy and gas chromatography were used to obtain the fluorescence spectra and fatty acid profile, respectively. Principal component analysis and 3-way partial least squares regression analysis were applied to analyze the data. The pure and adulterated samples were discriminated based on the total concentration of saturated fatty acids and unsaturated fatty acids, and also on the 3 major fluorophores: tryptophan, tocopherols, and riboflavin. Fluorescence spectroscopy was able to detect up to 5% of adulteration of vegetable oil into the butterfat. The saturated fatty acids showed higher predictability than the unsaturated fatty acids (R(2) = 0.73-0.92 vs. 0.20-0.65, respectively). The study demonstrated the high potential of fluorescence spectroscopy to rapidly detect adulteration of milk fat with vegetable oil, and discriminate commercial butter and milk according to the source of the fat. PMID:23415535

Ntakatsane, M P; Liu, X M; Zhou, P

2013-02-15

147

Toward High-Performance Communications Interfaces for Science Problem Solving  

NASA Astrophysics Data System (ADS)

From a theoretical viewpoint, educational interfaces that facilitate communicative actions involving representations central to a domain can maximize students' effort associated with constructing new schemas. In addition, interfaces that minimize working memory demands due to the interface per se, for example by mimicking existing non-digital work practice, can preserve students' attentional focus on their learning task. In this research, we asked the question: What type of interface input capabilities provide best support for science problem solving in both low- and high- performing students? High school students' ability to solve a diverse range of biology problems was compared over longitudinal sessions while they used: (1) hardcopy paper and pencil (2) a digital paper and pen interface (3) pen tablet interface, and (4) graphical tablet interface. Post-test evaluations revealed that time to solve problems, meta-cognitive control, solution correctness, and memory all were significantly enhanced when using the digital pen and paper interface, compared with tablet interfaces. The tangible pen and paper interface also was the only alternative that significantly facilitated skill acquisition in low-performing students. Paradoxically, all students nonetheless believed that the tablet interfaces provided best support for their performance, revealing a lack of self-awareness about how to use computational tools to best advantage. Implications are discussed for how pen interfaces can be optimized for future educational purposes, and for establishing technology fluency curricula to improve students' awareness of the impact of digital tools on their performance.

Oviatt, Sharon L.; Cohen, Adrienne O.

2010-12-01

148

The Investigation of Teacher Communication Practices in Virtual High School  

ERIC Educational Resources Information Center

Virtual schooling is an increasing trend for secondary education. Research of the communication practices in virtual schools has provided a myriad of suggestions for virtual school policies. Although transactional distance has been investigated in relation to certain aspects of the communication process, a small-scale qualitative study has not…

Belair, Marley

2011-01-01

149

The Investigation of Teacher Communication Practices in Virtual High School  

ERIC Educational Resources Information Center

|Virtual schooling is an increasing trend for secondary education. Research of the communication practices in virtual schools has provided a myriad of suggestions for virtual school policies. Although transactional distance has been investigated in relation to certain aspects of the communication process, a small-scale qualitative study has not…

Belair, Marley

2011-01-01

150

Short communication: intermediate prevalence of HIV type 1 primary antiretroviral resistance in Ceará State, Northeast Brazil.  

PubMed

Brazil is a large developing country where almost all FDA-licensed antiretrovirals are made available to more than 200,000 individuals under antiretroviral treatment. General primary HIV-1 resistance in Brazil is assumed to be low, but data are scarce, especially in the Northeast region. To evaluate the prevalence of primary HIV-1 antiretroviral resistance in the state of Ceará, Brazil, a cross-sectional prospective study of antiretroviral-naive HIV-1-infected individuals was performed between May 2008 and May 2009. Genomic sequences of reverse transcriptase and protease regions of the pol gene of HIV-1 using PCR products were obtained. Mutations related to resistance to NRTI, NNRTI, and PI were evaluated according to the WHO mutation list for primary resistance surveillance, which excludes common polymorphisms. Seventy-four individuals were evaluated (50% male) with a median age 30 years; 55.4% were men who have sex with men. Median CD4(+) T lymphocyte counts were 418 and 960 cells/mm(3) and the median viral loads were 4.41 and 4.46 log(10) RNA copies/ml for individuals older and younger that 18 years, respectively. Twenty-seven percent of patients were symptomatic. Five patients (6.8%) were recently infected, as detected by the BED test. The mutations 41L, 67N, 215D, 219Q, 101E, and 103N in the RT and 32I, 46I, 54V, 82T, and 90M, in the PR were identified in 9.5% of samples, more frequently in HIV subtype B (85.1%). A significant level of primary HIV resistance was detected in urban Northeast Brazil, a region geographically distant from the more highly populated and wealthier areas of Southeast Brazil, and this emphasizes the need for monitoring resistance in the studied area. PMID:20929346

Arruda, Erico; Simões, Leda; Sucupira, Cecília; Medeiros, Melissa; Arruda, Eurico; Diaz, Ricardo S; Lima, Aldo

2010-10-07

151

Short communication: oral lesions in HIV/AIDS patients undergoing HAART including efavirenz.  

PubMed

Oral lesions (OL) have an important prognostic value for HIV/AIDS patients. However, the behavior of OL in HIV/AIDS patients undergoing highly active antiretroviral therapy including efavirenz (HAART/EFV) has not been documented. Our objective was to establish the prevalence of OL in HIV/AIDS patients undergoing HAART/EFV and to compare it with the prevalence of OL in patients undergoing antiretroviral therapy including a protease inhibitor (HAART/PI). Seventy-three HIV/AIDS patients undergoing antiretroviral treatment for at least for 6 months at "La Raza" Medical Center's Internal Medicine Unit (IMSS, Mexico City) were included. To detect OL, a detailed examination of oral soft tissues was performed in each patient. Patient records recorded gender, seropositivity time, route of contagion, antiretroviral therapy type and duration, CD4 lymphocyte count/ml, and viral load. Two groups were formed: 38 patients receiving HAART/EFV [two nucleoside analogue reverse transcriptase inhibitors (NARTI) plus efavirenz] and 35 patients receiving HAART/PI (two NARTIs plus one PI). OL prevalence was established in each study group. The Chi-square test was applied (p < 0.05(IC95%)). OL prevalence in the HAART/EFV group (32%) was lower (p < 0.007) than in the HAART/PI group (63%). Candidosis was the most prevalent OL in both groups. Herpes labialis, HIV-associated necrotizing periodontitis, xerostomia, hairy leukoplakia, and nonspecific oral sores were identified. The highest prevalence for all OL was found in the HAART/PI group. These findings suggest that HIV/AIDS patients undergoing HAART/EFV show a lower prevalence of oral lesions than patients undergoing HAART/PI. PMID:18507528

Aquino-García, S I; Rivas, M A; Ceballos-Salobreña, A; Acosta-Gio, A E; Gaitán-Cepeda, L A

2008-06-01

152

Short Communication: Use of Raltegravir in Late-Presenting HIV-Infected Pregnant Women.  

PubMed

Abstract The risk of HIV-1 mother-to-child transmission (MTCT) is clearly correlated with the maternal HIV cell-free viral load (VL) at delivery. Preventing MTCT in late-presenting (after 28 weeks) HIV-infected pregnant women remains a clinical challenge, and ensuring a rapid decrease of maternal VL is an important preventive strategy. Raltegravir (RGV) has a higher first and second phase viral decay rate, has a high placental transfer, with a potential preloading effect for neonate, and demonstrates effective accumulation in cervicovaginal secretions. We report 14 cases in which RGV was used late in pregnancy for HIV-1 MTCT prophylaxis. All women were RGV naive and the prophylaxis regimens included RGV plus at least two other antiretroviral agents. At RGV initiation, the median gestational age was 36 weeks (range 34-38) and the median maternal plasma HIV-1 RNA viral load was 35,364 copies/ml (range 636-391,535). At delivery, the median gestational age was 38 weeks (range 37-40). The median exposure time to RGV was 17 days (range 7-32), with a mean maternal VL decay of 2.6 log. At delivery, seven women had undetectable (<50 copies/ml) VL, four had between 64 and 457 copies/ml, and in three VL was not available. All but one infant's HIV-RNA tests were negative at 1 and 3 months (one case of in utero MTCT). Raltegravir-containing antiretroviral regimens induced a rapid HIV-RNA decline in maternal VL at delivery, and were safe and effective in preventing MTCT for late-presenting, HIV-infected women. PMID:23731224

Nóbrega, Isabella; Travassos, Ana Gabriela; Haguihara, Tatiana; Amorim, Fábio; Brites, Carlos

2013-06-25

153

Recent developments in high-power short-wave mid-infrared semiconductor disk lasers  

NASA Astrophysics Data System (ADS)

Many applications exist for high performance lasers in the short-wave, mid-infrared spectral regime between 1.9 and 2.5?m - from long-range communications systems through to remote atmospheric gas sensing and pollution monitoring. However, a simple, efficient laser source offering the desired performance characteristics and flexibility has not been available. In the last few years considerable progress has been made in the development of optically-pumped (AlGaIn)(AsSb) quantum well semiconductor disk lasers emitting in the 2.X?m mid-infrared spectral region - continuous-wave and pulsed-pumped output power levels now exceed 6W and 16W respectively. Furthermore, singlefrequency operation with linewidths <4MHz and broad tunability of up to 170nm have also been demonstrated, all at near-diffraction-limited beam quality. Such performance metrics are only possible through the very best materials growth, a sound understanding of the design principles of these highly multi-layered devices and, importantly, the application of effective thermal management.

Burns, D.; Hopkins, J.-M.; Kemp, A. J.; Rösener, B.; Schulz, N.; Manz, C.; Köhler, K.; Rattunde, M.; Wagner, J.

2009-02-01

154

Adaptive Underwater Acoustic Communications  

Microsoft Academic Search

\\u000a Underwater wireless networks consist of mobile and static nodes, which usually communicate using the acoustic channel since\\u000a radio transmissions attenuate rapidly and optical communication is only suitable for short distances. The underwater acoustic\\u000a channel is plagued with issues of high transmission power requirements, rapidly changing channel characteristics, multi-path\\u000a echoes, possible high ambient noise, high and varying propagation delays. To achieve

Anuj Sehgal; Jürgen Schönwälder

2010-01-01

155

RF/photonic antenna for high-capacity wireless communications  

NASA Astrophysics Data System (ADS)

This paper proposes the integration of an antenna with a photodetector for high capacity wireless communications. The side-illuminated waveguide photodetector (WGPD) is used to convert the RF-modulated optical power into a microwave signal, which in turn is fed to an antenna. The WGPD is a standard p-i-n device grown on a semi-insulating InP substrate and fabricated using conventional techniques. The performance of this RF/photonic antenna in the frequency range 17-20 GHz is studied theoretically and experimentally. An equivalent circuit model for the WGPD is developed to estimate the photodetector impedance as a function of frequency to assist in the impedance matching between the photodetector and the antenna. The agreement between measurement and circuit model results for the WGPD impedance is very good. It is envisioned that a large number of such RF/Photonic antenna elements could be networked together into a star configuration, feeding in and out of a radio hub.

Khodier, Majid; Christodoulou, Christos G.; Tzeremes, George; Yu, Paul K.

2002-06-01

156

Short Distance Wireless Communications  

Microsoft Academic Search

\\u000a Since the publication of the first biomedical swallowable telemetry device in 1957, an immense evolution has taken place in\\u000a biomedical monitoring, stimulation and instrumentation, that would have been impossible without the use of wireless information\\u000a transmission. The first section gives an overview of wireless methods for transmitting information to and from biomedical\\u000a implants, followed by a practical introduction on analog

Robert Puers; Jef Thoné

157

Multiplexed communication over a high-speed quantum channel  

SciTech Connect

In quantum information systems it is of particular interest to consider the best way in which to use the nonclassical resources consumed by that system. Quantum communication protocols are integral to quantum information systems and are among the most promising near-term applications of quantum information science. Here we show that a multiplexed, digital quantum communications system supported by a comb of vacuum squeezing has a greater channel capacity per photon than a source of broadband squeezing with the same analog band width. We report on the time-resolved, simultaneous observation of the first dozen teeth in a 2.4-GHz comb of vacuum squeezing produced by a subthreshold optical parametric oscillator, as required for such a quantum communications channel. We also demonstrate multiplexed communication on that channel.

Heurs, M.; Webb, J. G.; Dunlop, A. E.; Harb, C. C.; Huntington, E. H. [Centre for Quantum Computer Technology, School of Information Technology and Electrical Engineering, University College, University of New South Wales, Canberra, Australian Capitol Territory 2600 (Australia); Ralph, T. C. [Centre for Quantum Computer Technology, Department of Physics, University of Queensland, St. Lucia, Brisbane, Queensland 4072 (Australia)

2010-03-15

158

Design and Operation of a High Level Multicomputer Communications Package.  

National Technical Information Service (NTIS)

The need for a means of communication between tasks in either a multiprogramming or time-sharing environment becomes necessary when one wants to coordinate the activities of several real time interdependent tasks. Likewise, when a computing system is comp...

P. R. Bodenstab

1976-01-01

159

INFORMATION AND COMMUNICATION TECHNOLOGIES AND HIGH EDUCATION TEACHERS TRAINING  

Microsoft Academic Search

This paper explores the relationship between Information and Communication Technology (ICT) and training in the Higher Education Sector. We have tried to understand the basic dimensions of ICT HE teacher training in the light of the most \\

ADEL BEN YOUSSEF

160

Short-baseline oscillations of high-energy neutrinos  

NASA Astrophysics Data System (ADS)

In the last decade neutrinos provided many impressive results/surprises and their relevance in the understanding of the "Next Physics Scenario" should be largely acknowledged. Neutrino oscillations have so far established a beautiful picture, consistent with the mixing of three physical neutrino ?e,?? and ?? and mass eigenstates ?1,?2 and ?3. However it might very well be that neutrinos be something other than just a neutral counterpart of charged leptons (in line with the quantitative and incomprehensible differences between the leptonic and quark sectors) leaving room for additional neutrinos which do not see the ordinary electro-weak interactions but still follow mixing oscillations with ordinary neutrinos. Several "anomalies" have been collected in the last decade, too, not experimentally confirmed, yet, which may correspond to the presence of larger squared mass differences related to additional neutrino states, with presumably some kind of "sterile" nature. We will focus on the "short term" quest for the possible existence of sterile neutrinos with a new experiment to be placed in the truly new project at CERN of a Short-Base-Line Neutrino beam Facility (SBLNF).

Stanco, Luca

2013-04-01

161

10 Gb/s optical carrier distributed network with W-band (0.1 THz) short-reach wireless communication system  

NASA Astrophysics Data System (ADS)

Millimeter-wave (mm-wave) operated in W-band (75 GHz-0.11 THz) is of particular interests, since this frequency band can carry signals at much higher data rates. We demonstrate a 10 Gb/s optical carrier-distributed network with the wireless communication system. The mm-wave signal at carrier frequency of 0.1 THz is generated by a high speed near-ballistic uni-traveling carrier photodiode (NBUTC-PD) based transmitter (Tx), which is optically excited by optical short pulses. The optical pulse source is produced from a self-developed photonic mm-wave waveform generator (PMWG), which allows spectral line-by-line pulse shaping. Hence these optical pulses have high tolerance to fiber chromatic dispersion. The W-band 10 Gb/s wireless data is transmitted and received via a pair of horn antennas. The received 10 Gb/s data is envelope-detected and then used to drive an optical modulator at the remote antenna unit (RAU) to produce the upstream signal sending back to the central office (CO). 20 km single mode fiber (SMF) error free transmission is achieved. Analysis about the optimum repetition rate of the optical pulse source and the transmission performance of the upstream signal are also performed and discussed.

Chow, C. W.; Yang, L. G.; Yeh, C. H.; Huang, C. B.; Shi, J. W.; Pan, C. L.

2012-10-01

162

High speed short wave infrared (SWIR) imaging and range gating cameras  

NASA Astrophysics Data System (ADS)

Imaging in the Short Wave Infrared (SWIR) provides unique surveillance capabilities, both with passive illumination from the night glow in the atmosphere or with active illumination from covert LED or eye-safe lasers. Spectral effects specific to the 0.9 to 1.7 um wavelength range reveal camouflage and chemical signatures of ordinance. The longer wavelength range also improves image resolution over visible cameras in foggy or dusty environments. Increased military interest in cameras that image all laser range finders and target designators on the battlefield has driven development of a new class of uncooled InGaAs cameras with higher resolution and larger field of view than previously available. Current and upcoming needs include: imaging in all lighting conditions, from direct sunlight to partial starlight while using minimal power; range gating the camera to image through obscurants or beyond unimportant objects; and high speed capture of muzzle flare, projectile tracking, guide star and communications laser-beam tracking and wavefront correction. This paper will present images from new COTS cameras now available to address these needs and discuss the technology roadmap for further improvements.

Malchow, Douglas; Battaglia, Jesse; Brubaker, Robert; Ettenberg, Martin

2007-04-01

163

X-rays from high-intensity, short-pulse laser interaction with solids  

NASA Astrophysics Data System (ADS)

Laser pulses with high intensity (up to 1018 W/cm2) and short duration (100 fs) were focused on solids. The result was highly ionized material and hot electrons, along with the emission of short pulse x-rays and unicycle electromagnetic pulses with subpicosecond duration.

Falcone, R. W.; Gordon, S. P.; Hamster, H.; Sullivan, A.

1993-10-01

164

Proton upset testing of commercial high-speed optical Tx\\/Rx for intersatellite communication links  

Microsoft Academic Search

Commercial high speed fiber optic transmitters and receivers were tested in a high energy proton environment at the Crocker Nuclear Laboratory to determine the transient impact of the space proton environment on a simulated communications link. The link was designed to simulate free-space communication between satellites. The transmit\\/receive bit error ratio was used as the evaluation metric. Individual electronic components

Kyle M. Miller; Tim O'Connor; Donald A. Thompson; John Rizo; Robert W. Kaliski

1999-01-01

165

An integrated optical\\/acoustic communication system for seafloor observatories: A field test of high data rate communications at CORK 857D  

Microsoft Academic Search

We report the successful deployment and testing of an underwater optical communication system that provides high data rate communications over a range of 100 meters from a deep sea borehole observatory located in the northeast Pacific. Optical underwater communications offers many advantages over acoustic or underwater wet mateable connections (UWMC). UMWCs requires periodic visits from a submersible or ROV to

M. Tivey; N. Farr; J. Ware; C. Pontbriand

2010-01-01

166

A short educational intervention on communication skills improves the quality of screening for Chlamydia in GPs in Belgium: a cluster randomised controlled trial.  

PubMed

An accurate algorithm for screening for chlamydial infections is available in general practice, but GPs experience numerous barriers to sexually transmitted infections (STI) counselling. In this study we assessed if a short educational package, under the form of a commented video footage on communication skills, was helpful in implementing the screening strategy. A cluster randomised controlled trial was carried out in 36 general practitioners in Antwerp, Belgium. Main outcome measures were: number of patients included in the risk assessment, number of patients tested, and proportion of appropriately tested patients. The results show that GPs in the intervention group did not include more patients overall, but that the quality of the screening process was significantly better (81.6% versus 56.2% appropriate tests, P = 0.02). Conclusively, GPs who participated in a short educational package on communication skills, selected eligible candidates for screening more accurately and decreased the risk of overscreening. PMID:15797158

Verhoeven, Veronique; Avonts, Dirk; Vermeire, Etienne; Debaene, Luc; Van Royen, Paul

2005-04-01

167

Whole-Genome Sequencing and Assembly with High-Throughput, Short-Read Technologies  

Microsoft Academic Search

While recently developed short-read sequencing technologies may dramatically reduce the sequencing cost and eventually achieve the $1000 goal for re-sequencing, their limitations prevent the de novo sequencing of eukaryotic genomes with the standard shotgun sequencing protocol. We present SHRAP (SHort Read Assembly Protocol), a sequencing protocol and assembly methodology that utilizes high-throughput short-read technologies. We describe a variation on hierarchical

Andreas Sundquist; Mostafa Ronaghi; Haixu Tang; Pavel Pevzner; Serafim Batzoglou

2007-01-01

168

Superdense wavelength-division multiplexing in high-bit-rate multichannel fibreoptic communication links  

SciTech Connect

A new flat-top format for highly spectrally efficient fibreoptic data communication links is studied. Analytic expressions are obtained for the averaged power spectrum of an optical signal and a strong dependence of the power spectrum shape on the frequency shift of an optical filter with respect to the centre of a specified channel is demonstrated. A direct numerical simulation of multichannel optical communication links based on this format is performed. (fibreoptic data communication)

Shapiro, Elena G [Institute of Automation and Electrometry, Siberian Branch, Russian Academy of Sciences, Novosibirsk (Russian Federation); Fedoruk, Mikhail P [Institute of Computational Techologies, Siberian Branch of the Russian Academy of Sciences, Novosibirsk (Russian Federation); Zakharyuta, M V [Novosibirsk State University, Novosibirsk (Russian Federation)

2006-06-30

169

Experimental study of propagation characteristics for wireless communications in high-speed train cars  

Microsoft Academic Search

This paper describes the measurement results of propagation loss characteristics in high-speed train cars. We focus on the propagation loss in intra-car communications using a 2-GHz band and inter-car communications using a 5-GHz band. The measurement campaign is carried out using real train cars under both running and non-running conditions. The measurement results for intra-car communications indicate a waveguide effect

N. Kita; T. Ito; S. Yokoyama; Ming-Chien Tseng; Y. Sagawa; M. Ogasawara; M. Nakatsugawa

2009-01-01

170

Robust Team-Play in Highly Uncertain Environments (Short Paper)  

Microsoft Academic Search

Eective teamwork in highly dynamic environments requires a delicate balance between giving agents the autonomy to act and react on their own and restricting that autonomy so that the agents do not work at cross purposes. In this article we describe the problems involved in coordinating behavior based upon a highly dynamic object, a soccer ball, for agents with sensing

Henry Work; Eric Chown; Tucker Hermans; Jesse Butterfield

171

A Power-Efficient Clock and Data Recovery Circuit in 0.18 ?m CMOS Technology for MultiChannel Short-Haul Optical Data Communication  

Microsoft Academic Search

This paper studies the specifications of gated-oscillator-based clock and data recovery circuits (GO CDRs) designed for short haul optical data communication systems. Jitter tolerance (JTOL) and frequency tolerance (FTOL) are analyzed and modeled as two main design parameters for the proposed topology to explore the main tradeoffs in design of low-power GO CDRs. Based on this approach, a top-down design

Armin Tajalli; Paul Muller; Yusuf Leblebici

2007-01-01

172

An Investigation of Communication in Virtual High Schools  

ERIC Educational Resources Information Center

Virtual schooling is an increasing trend for secondary education. Research of the communication practices in virtual schools has provided a myriad of suggestions for virtual school policies. The purpose of this qualitative study was to investigate the activities and processes involved in the daily rituals of virtual school teachers and learners…

Belair, Marley

2012-01-01

173

High precision electromagnetic field sensors for monitoring communications devices  

Microsoft Academic Search

Presents computer simulation and experimental aspects towards the development of passive, all-dielectric, electro-optic and magneto-optic sensors based an the Pockel's and Faraday effects, respectively. Semiconductor crystals, laser diode and fibre optic technology will enable the measurement of electromagnetic fields from communications devices at frequencies up to 2 GHz

M. BERWICKt; S. R. Cvetkovic; F. V. Cecelia; W. Balachandran

1994-01-01

174

High-Tech PR: Five Case Studies in Computerized Communication.  

ERIC Educational Resources Information Center

|Use of computer technology for specialized communication networks at University of California (Oakland), Lafayette College (Pennsylvania), Carnegie Mellon University (Pennsylvania), the University of Wisconsin at Eau Claire, and the State University of New York at Stony Brook is described. The systems feature different forms of internal and…

Malaspina, Rick; And Others

1993-01-01

175

When Are High-Tech Communicators Effective in Parkinson's Disease?  

ERIC Educational Resources Information Center

|This report describes a 63-year-old woman with Parkinson's disease showing loss of intelligibility of speech and severely impaired handwriting, despite undergoing physical and speech therapies. As the patient had sufficient residual motor abilities and adequate cognitive function and motivation, a computer-based communication aid with a software…

Ferriero, Giorgio; Caligari, Marco; Ronconi, Gianpaolo; Franchignoni, Franco

2012-01-01

176

Toward High-Performance Communications Interfaces for Science Problem Solving  

ERIC Educational Resources Information Center

From a theoretical viewpoint, educational interfaces that facilitate communicative actions involving representations central to a domain can maximize students' effort associated with constructing new schemas. In addition, interfaces that minimize working memory demands due to the interface per se, for example by mimicking existing non-digital work…

Oviatt, Sharon L.; Cohen, Adrienne O.

2010-01-01

177

Building reliable, high-performance communication systems from components  

Microsoft Academic Search

Although building systems from components has attractions, this approach also has problems. Can we be sure that a certain configuration of components is correct? Can it perform as well as a monolithic system? Our paper answers these questions for the Ensemble communication architecture by showing how, with help of the Nuprl formal system, configurations may be checked against specifications, and

Xiaoming Liu; Christoph Kreitz; Robbert van Renesse; Jason Hickey; Mark Hayden; Kenneth P. Birman; Robert L. Constable

1999-01-01

178

Short and Long-Term Impacts of Biotechnology Education on Professionals Who Communicate Science to the Public  

ERIC Educational Resources Information Center

|Consumer acceptance or rejection of biotechnology is often shaped by information prepared by communicators with varying levels of scientific knowledge, awareness, and acceptance. This study compared the prior, post-workshop, and sustained (1 year) biotechnology awareness, acceptance, and attitudes of professionals who communicate biotechnology to…

Fritz, Susan M.; Ward, Sarah M.; Byrne, Pat F.; Namuth, Deana M.; Egger, Valerie A.

2004-01-01

179

LiMIC: Support for High-Performance MPI Intra-node Communication on Linux Cluster  

Microsoft Academic Search

High performance intra-node communication support for MPI applications is critical for achieving best perfor- mance from clusters of SMP workstations. Present day MPI stacks cannot make use of operating system kernel support for intra-node communication. This is primarily due to the lack of an efficient, portable, stable and MPI friendly inter- face to access the kernel functions. In this paper

Hyun-wook Jin; Sayantan Sur; Lei Chai; Dhabaleswar K. Panda

2005-01-01

180

Investigation of a Photovoltaic/Battery Hybrid System for Powering the High Arctic Data Communications System.  

National Technical Information Service (NTIS)

The High Arctic Data Communications System (HADCS) was established to provide reliable communication between CFS Alert and Ottawa. This system includes a ground link from Alert to Eureka and a satellite link from Eureka to Ottawa. The ground link is neces...

C. L. Gardner

1989-01-01

181

Signal processing ASIC requirements for high-speed wireless data communications  

Microsoft Academic Search

The role of VLSI ASIC technology in the realization of future wireless communication systems is key. New architectures and circuit techniques can be leveraged to provide significant performance improvement in high-speed wireless data communication systems operating at symbol rates in excess of a few MBaud. VLSI ASIC research can help deliver the required signal processing power to realize sophisticated baseband

Babak Daneshrad

1998-01-01

182

Communication Requirements and Interconnect Optimization for High-End Scientific Applications  

Microsoft Academic Search

The path toward realizing next-generation petascale and exascale computing is increasingly dependent on building supercomputers with unprecedented numbers of processors. To prevent the interconnect from dominating the overall cost of these ultrascale systems, there is a critical need for scalable interconnects that capture the communication requirements of ultrascale applications. It is, therefore, essential to understand high-end application communication characteristics across

Shoaib Kamil; Leonid Oliker; Ali Pinar; John Shalf

2010-01-01

183

Using mobile communication technology in high school education: Motivation, pressure, and learning performance  

Microsoft Academic Search

Motivation and pressure are considered two factors impacting vocational senior high school student learning. New communication technology, especially mobile communication technology, is supposed to be effective in encouraging inter- action between the student and the instructor and improving learning efficiency. Social presence and information richness theory was applied to analyze the media and their impacts on the instruction process firstly.

Pei-luen Patrick Rau; Qin Gao; Li-mei Wu

2008-01-01

184

Using Mobile Communication Technology in High School Education: Motivation, Pressure, and Learning Performance  

ERIC Educational Resources Information Center

|Motivation and pressure are considered two factors impacting vocational senior high school student learning. New communication technology, especially mobile communication technology, is supposed to be effective in encouraging interaction between the student and the instructor and improving learning efficiency. Social presence and information…

Rau, Pei-Luen Patrick; Gao, Qin; Wu, Li-Mei

2008-01-01

185

Cultural terms for communication events among some American high school adolescents  

Microsoft Academic Search

Through ethnographic interviewing, participant observation, and cluster analysis of perceptual judgment data, this study examines the natural language descriptions employed by some American high school adolescents in talking about the kinds of communication events they experience in everyday life and the underlying semantic dimensions by which these adolescents perceptually organize this domain. Adolescents described communication events through use of setting,

Leslie A. Baxter; Daena Goldsmith

1990-01-01

186

Quantum secure direct communication with high-dimension quantum superdense coding  

SciTech Connect

A protocol for quantum secure direct communication with quantum superdense coding is proposed. It combines the ideas of block transmission, the ping-pong quantum secure direct communication protocol, and quantum superdense coding. It has the advantage of being secure and of high source capacity.

Wang Chuan; Li Yansong; Liu Xiaoshu [Key Laboratory for Quantum Information and Measurements, and Department of Physics, Tsinghua University, Beijing 100084 (China); Deng Fuguo [Key Laboratory for Quantum Information and Measurements, and Department of Physics, Tsinghua University, Beijing 100084 (China); Key Laboratory of Beam Technology and Materials Modification of Ministry of Education, and Institute of Low Energy Nuclear Physics, Beijing Normal University, Beijing 100875 (China); Long Guilu [Key Laboratory for Quantum Information and Measurements, and Department of Physics, Tsinghua University, Beijing 100084 (China); Key Laboratory for Atomic and Molecular NanoSciences, Tsinghua University, Beijing 100084 (China)

2005-04-01

187

High-performance multi-queue buffers for VLSI communications switches  

Microsoft Academic Search

Small nxn switches are key components of multistage interconnection networks used in multiprocessors as well as in the communication coprocessors used in multicomputers. The design of the internal buffers in these switches is of critical importance for achieving high throughput low latency communication. We discuss several buffer structures and compare them in terms of implementation complexity and their ability to

Yuval Tamir; Gregory L. Frazier

1988-01-01

188

Computer Mediated Communication: Providing Pastoral Care to Youth in “A High Tech” World  

Microsoft Academic Search

This study used a hermeneutical methodology to explore how Computer Mediated Communication (CMC) can be used to provide pastoral care to youth in a high tech world. The research was motivated by the writers desire to find ways to be in communication with youth and provide pastoral care to them during their adolescent years. The thesis will explore computer mediated

Tanya L. Ramer

2008-01-01

189

Short-pulse, high-intensity lasers at Los Alamos  

SciTech Connect

Advances in ultrafast lasers and optical amplifiers have spurred the development of terawatt-class laser systems capable of delivering focal spot intensities approaching 10{sup 20} W/cm{sup 2}. At these extremely high intensities, the optical field strength is more than twenty times larger than the Bohr electric field, permitting investigations of the optical properties of matter in a previously unexplored regime. The authors describe two laser systems for high intensity laser interaction experiments: The first is a terawatt system based on amplification of femtosecond pulses in XeCl which yields 250 mJ in 275 fs and routinely produces intensifies on target in excess of 10{sup 18} W/cm{sup 2}. The second system is based on chirped pulse amplification of 100-fs pulses in Ti:sapphire.

Taylor, A.J.; Roberts, J.P.; Rodriguez, G.; Fulton, R.D.; Kyrala, G.A.; Schappert, G.T.

1994-03-01

190

Impact of a Program to Facilitate Mother-Infant Communication in High-Risk Families of High-Risk Infants.  

ERIC Educational Resources Information Center

Mothers in the Mother-Infant Communication Project (MICP), designed to facilitate caregivers' uses of communicative interaction strategies with their high-risk infants, scored better than comparison mothers on caregiving environment quality. Children of MICP mothers who received a group experience in addition to home visits performed better on…

Haney, Michele; Klein, M. Diane

1993-01-01

191

Short-term, high-efficiency expression of transfected DNA.  

PubMed Central

We have achieved high-efficiency uptake and expression of foreign DNA in mouse Ltk- cells by modifying the DEAE-dextran-mediated transfection method of McCutchan and Pagano (J. Natl. Cancer Inst. 42:351-357, 1968) to include an initial incubation at elevated pH followed by a shock treatment with dimethyl sulfoxide. Up to 80% of mouse Ltk- cells transfected with the herpes simplex virus thymidine kinase gene expressed thymidine kinase as measured by autoradiography. Images

Sussman, D J; Milman, G

1984-01-01

192

FAST TRACK COMMUNICATION: The collision of multimode dromions and a firewall in the two-component long-wave-short-wave resonance interaction equation  

NASA Astrophysics Data System (ADS)

In this communication, we investigate the two-component long-wave-short-wave resonance interaction equation and show that it admits the Painlevé property. We then suitably exploit the recently developed truncated Painlevé approach to generate exponentially localized solutions for the short-wave components S(1) and S(2) while the long wave L admits a line soliton only. The exponentially localized solutions driving the short waves S(1) and S(2) in the y-direction are endowed with different energies (intensities) and are called 'multimode dromions'. We also observe that the multimode dromions suffer from intramodal inelastic collision while the existence of a firewall across the modes prevents the switching of energy between the modes.

Radha, R.; Senthil Kumar, C.; Lakshmanan, M.; Gilson, C. R.

2009-03-01

193

Toward High-Performance Communications Interfaces for Science Problem Solving  

Microsoft Academic Search

From a theoretical viewpoint, educational interfaces that facilitate communicative actions involving representations central\\u000a to a domain can maximize students’ effort associated with constructing new schemas. In addition, interfaces that minimize\\u000a working memory demands due to the interface per se, for example by mimicking existing non-digital work practice, can preserve\\u000a students’ attentional focus on their learning task. In this research, we

Sharon L. OviattAdrienne; Adrienne O. Cohen

2010-01-01

194

The High-Performance Computing and Communications Program, the National Information Infrastructure and Health Care  

Microsoft Academic Search

The High-Performance Computing and Communications (HPCC) program is a multiagency federal effort to advance the state of computing and communications and to provide the technologic platform on which the National Information Infrastructure (NII) can be built. The HPCC program supports the development of high-speed computers, high-speed telecommunications, related software and algorithms, education and training, and information infrastructure technology and applications.

Donald A B Lindberg; Betsy L Humphreys

1995-01-01

195

High-rate synthetic aperture communications in shallow water.  

PubMed

Time reversal communication exploits spatial diversity to achieve spatial and temporal focusing in complex ocean environments. Spatial diversity can be provided easily by a vertical array in a waveguide. Alternatively, spatial diversity can be obtained from a virtual horizontal array generated by two elements, a transmitter and a receiver, due to relative motion between them, referred to as a synthetic aperture. This paper presents coherent synthetic aperture communication results from at-sea experiments conducted in two different frequency bands: (1) 2-4 kHz and (2) 8-20 kHz. Case (1) employs binary-phase shift-keying modulation, while case (2) involves up to eight-phase shift keying modulation with a data rate of 30 kbits/s divided by the number of transmissions (diversity) to be accumulated. The receiver utilizes time reversal diversity combining followed by a single channel equalizer, with frequent channel updates to accommodate the time-varying channel due to coupling of space and time in the presence of motion. Two to five consecutive transmissions from a source moving at 4 kts over 3-6 km range in shallow water are combined successfully after Doppler compensation, confirming the feasibility of coherent synthetic aperture communications using time reversal. PMID:20000919

Song, H C; Hodgkiss, W S; Kuperman, W A; Akal, T; Stevenson, M

2009-12-01

196

High-peak-power short-pulse fiber laser for materials processing  

Microsoft Academic Search

High-speed, high-resolution materials processing strongly benefits from optical sources that deliver high peak power in short, high-repetition-rate pulses of excellent beam quality. These sources are also of interest for achieving high average power at nonlinearly-generated wavelengths. Until recently, high peak power, high-repetition-rate pulses have only been available from solid-state lasers. Fiber lasers and amplifiers offer significant advantages over solid-state lasers

Alison M. Thomas; Deborah A. Alterman; Mark S. Bowers

2009-01-01

197

High Bandwidth Short Stroke Rotary Fast Tool Servo  

SciTech Connect

This paper presents the design and performance of a new rotary fast tool servo (FTS) capable of developing the 40 g's tool tip acceleration required to follow a 5 micron PV sinusoidal surface at 2 kHz with a planned accuracy of 50 nm, and having a full stroke of 50 micron PV at lower frequencies. Tests with de-rated power supplies have demonstrated a closed-loop unity-gain bandwidth of 2 kHz with 20 g's tool acceleration, and we expect to achieve 40 g's with supplies providing {+-} 16 Amp to the Lorentz force actuator. The use of a fast tool servo with a diamond turning machine for producing non-axisymmetric or textured surfaces on a workpiece is well known. Our new rotary FTS was designed to specifically accommodate fabricating prescription textured surfaces on 5 mm diameter spherical target components for High Energy Density Physics experiments on the National Ignition Facility Laser (NIF).

Montesanti, R C; Trumper, D L

2003-08-22

198

Evolutionary Design on FCC Reactors Driven by the High Temperature and Short Contact Time Demands  

Microsoft Academic Search

The influence of high temperature and short contact time on FCC is discussed elaborately. Some novel technologies in feed distribution, riser termination system, and some new FCC processes based on the reactor's innovation are introduced in detail. Various kinds of technologies which are propitious to the realization of high-temperature and short-contact time can effectively lead to better a gas-solids contact,

Gang Wang; Jin-Sen Gao; Chun-Ming Xu

2004-01-01

199

HF (High Frequency) Communications Frequency-Management Procedure for Forecasting the Frequency of Optimum Transmission.  

National Technical Information Service (NTIS)

This report describes a procedure for forecasting the Frequency of Optimum Transmission (FOT) on a high-frequency communications path when the Maximum Observable Frequency (MOF) on another path and an historical record of the correlations of MOFs measured...

M. Daehler

1984-01-01

200

High performance computing and communications: Advancing the frontiers of information technology.  

National Technical Information Service (NTIS)

This report, which supplements the President's Fiscal Year 1997 Budget, describes the interagency High Performance Computing and Communications (HPCC) Program. The HPCC Program will celebrate its fifth anniversary in October 1996 with an impressive array ...

1997-01-01

201

Opportunities and Challenges in Utilizing Millimeter-Wave Spectrum for High Speed Wireless Communications  

Microsoft Academic Search

The 60 GHz band has emerged as an international spectrum opportunity for short-range wireless communication networks. In this paper, technology trends that can impact the commercial deployment of systems utilizing millimeter-wave frequency bands are discussed. Millimeter-wave frequency bands have historically been costly to utilize and traditionally used almost exclusively for government and non-consumer products. Recent and ongoing advances in semiconductor

Rudy Emrick; Steve Franson; John Holmes; Bruce Bosco; Steve Rockwell

2007-01-01

202

Framework and Research Methodology of Short-Timescale Pulsed Power Phenomena in High-Voltage and High-Power Converters  

Microsoft Academic Search

Various short-timescale transients exist in power electronic converters, particularly in high-voltage and high-power systems. The timescales of these transients are from nanoseconds to microseconds, including a switching transition of power semiconductor devices, commutating processes, and drive signal transmissions. These transient processes directly affect the performance and reliability of power electronic systems. Therefore, it is necessary to study these short-timescale processes.

Hua Bai; Zhengming Zhao; Chris Mi

2009-01-01

203

Organizational Communication and Culture: A Study of 10 Italian High Technology Companies  

Microsoft Academic Search

An important contribution of this research is the testing in international envi ronments of communication and culture models previously developed within U.S.A. high-technology organizations. Specifically, this research demonstrates that relationships among organizational culture themes, employee values, organizational communication activities, and perceptions of a variety of organi zational outcomes are similar but not identical for U.S.A. and European high- technology organizations.

Donald Dean Morley; Pamela Shockley-Zalabak; Ruggero Cesaria

1997-01-01

204

Communications and entertainment onboard a high-speed public transport system  

Microsoft Academic Search

This article discusses architectural design at the conceptual\\/functional level of communication and entertainment services onboard a high-speed public transport system, such as a high-speed train, a transoceanic cruise ship, or even a mid- to long-range airplane. Existing commercial mobile communication services, such as AMPS and GSM, are inaccessible to passengers onboard these public transport systems. A hierarchical architecture is laid

Kun-De Lin; Jin-Fu Chang

2002-01-01

205

An Adaptive Compulsory Protocol for Basic Communication in Highly Changing Ad hoc Mobile Networks  

Microsoft Academic Search

In this paper we study the problem of basic communication in ad-hoc mobile networks where the deployment area changes in a highly dynamic way and is unknown. We call such networks highly changing ad-hoc mobile networks. For such networks we investigate an efficient communication protocol which extends the idea (introduced in [4, 6]) of exploiting the co-ordinated motion of a

Ioannis Chatzigiannakis; Sotiris E. Nikoletseas

2002-01-01

206

High-speed CMOS optical communication using silicon light emitters  

NASA Astrophysics Data System (ADS)

The idea of moving CMOS into the mainstream optical domain remains an attractive one. In this paper we discuss our recent advances towards a complete silicon optical communication solution. We prove that transmission of baseband data at multiples of megabits per second rates are possible using improved silicon light sources in a completely native standard CMOS process with no post processing. The CMOS die is aligned to a fiber end and the light sources are directly modulated. An optical signal is generated and transmitted to a silicon Avalanche Photodiode (APD) module, received and recovered. Signal detectability is proven through eye diagram measurements. The results show an improvement of more than tenfold over our previous results, also demonstrating the fastest optical communication from standard CMOS light sources. This paper presents an all silicon optical data link capable of 2 Mb/s at a bit error rate of 10-10, or alternatively 1 Mb/s at a bit error rate of 10-14. As the devices are not operating at their intrinsic switching speed limit, we believe that even higher transmission rates are possible with complete integration of all components in CMOS.

Goosen, Marius E.; Venter, Petrus J.; Du Plessis, Monuko; Nell, Ilse J.; Bogalecki, Alfons W.; Rademeyer, Pieter

2011-02-01

207

Ultra high bit rate all optical communication system  

NASA Astrophysics Data System (ADS)

A system that uses all optical elements for transmission, regeneration and reception of solitons in point-to-point, broadcast, ring and multi-user trunk type communication systems. Soliton pulses from an optical clock source are modulated by optical data pulses in an optical modulator producing a modulated channel of data pulses. Several channels are combined by an optical multiplexer into a network optical bit stream. This stream is carried by an optical fiber and one or more of optical regenerators which recover the system clock and regenerate the signal with the recovered system clock rather than just amplifying the signal. Each of the regenerators can, in addition to regenerating the data, act as part of a data drop or insert node in a ring network where the node can synchronously remove data from or insert data into the stream. Intermediate nodes can include packet drop/replace nodes if the network is a packet type network.

Duling, Irl N.; Easman, Ronald D.

1994-01-01

208

Generation of Radiation from Interaction Between Ultra Short Pulse Ultra High Power Laser and Magnetized Plasma  

Microsoft Academic Search

Investigation on electro-magnetic (EM) radiation due to the interaction of ultra-short terra-watt laser is presented. When high power and short laser pulse is focused in the plasma, the plasma wake field can be generated. Characteristics of such wake field is modified in the presence of magnetic field and rotational components of plasma electron motion, consequently it can emit the radiation.

Hajime Noda; Parchamy Homaira; Kobayashi Kazuhiro; Yugami Noboru

2004-01-01

209

Experimental demonstration of 10 Gb/s multi-level carrier-less amplitude and phase modulation for short range optical communication systems.  

PubMed

Carrier-less amplitude and phase (CAP) modulation can be a good candidate for short range optical communications for considerable computational complexity reduction and simple system structure. In this paper, a detailed investigation on the digital filters in CAP modulation system is presented. An adaptive equalizer based on cascaded multi-modulus algorithm (CMMA) is used for the demodulation at the receiver. The impact of digital filter taps on system performance is investigated through comprehensive simulations and a 10 Gb/s CAP16 modulation system is demonstrated experimentally. The BER performance for different length of fiber link is measured. Compared with back-to-back (BTB) transmissions, 2 dB and 3.5 dB receiver power penalty are observed at BER of 10(-3) for 20 km and 40 km fiber link respectively. It clearly demonstrates the feasibility of the CAP16 modulation for the short range transmission systems. PMID:23482215

Tao, Li; Wang, Yiguang; Gao, Yuliang; Lau, Alan Pak Tao; Chi, Nan; Lu, Chao

2013-03-11

210

Short communication Boron neutron capture therapy of the rat 9L gliosarcoma: evaluation of the effects of shark cartilage  

Microsoft Academic Search

A number of anti-angiogenic substances are now under evaluation, both experimentally and clinically, as potential agents for the treatment of cancer. It has recently been demonstrated that anti-angiogenic agents can increase the therapeutic potential of photon irradiation in a range of tumour models. In the present communication a preliminary assessment is made of the effects of shark cartilage on the

G M MORRIS; J A CODERRE; P L MICCA; D T LOMBARDO; J W HOPEWELL

2000-01-01

211

Short communication Pressure-time cell death threshold for albino rat skeletal muscles as related to pressure sore biomechanics  

Microsoft Academic Search

Deep pressure sores (DPS) are associated with inadequate soft tissue perfusion and excessive tissue deformation over critical time durations, as well as with ischemia-reperfusion cycles and deficiency of the lymphatic system. Muscle tissue shows the lowest tolerance to pressure injuries, compared with more superficial tissues. In this communication, we present new histopathology data for muscle tissue of albino (Sprague-Dawley) rats

Eran Linder-Ganz; Santiego Engelberg; Mickey Scheinowitz; Amit Gefen

212

High Performance Relay Mechanism for MPI Communication Libraries Run on Multiple Private IP Address Clusters  

Microsoft Academic Search

Abstract— We,have,been,developing,a Grid-enabled,MPI communication library called GridMPI, which is designed to run,on,multiple,clusters,connected,to a wide-area,network. Some of these clusters may use private IP addresses. Therefore, some,mechanism,to enable,communication,between,private,IP address,clusters is required. Such a mechanism,should,be widely adoptable, and should provide high communication performance. In this paper, we propose a message relay mechanism to support private IP address,clusters in the manner,of the Interoperable MPI

Ryousei Takano; Motohiko Matsuda; Tomohiro Kudoh; Yuetsu Kodama; Fumihiro Okazaki; Yutaka Ishikawa; Yasufumi Yoshizawa

2008-01-01

213

The 2 GHz high temperature superconducting receiver equipment for mobile communications  

Microsoft Academic Search

An ultra low noise and highly selective, experimental 2 GHz band cryogenic receiver front end (CRFE) has been newly developed for mobile communication base stations. It utilizes a high-Q superconducting filter, a very low noise cryogenic amplifier, and a highly reliable cooler that is very compact. The equivalent noise temperature (Teq) of the CRFE is less than 50 K (0.69

K. Satoh; T. Mimura; S. Narahashi; T. Nojima

2001-01-01

214

New variable limit super high speed communication possibility for dynamic media  

Microsoft Academic Search

Based upon author proposed multichannel multidimensional optimal grid transformation technique (-Emistical dynamic mapping) and variable Emistical super high speed dynamics, this paper analyzes variable super high speed communication for reversible and bidirectional GAMA dynamic media. The speed limit E could be between slow speed to infinite squared speed, mid-ranges being high, variable, fluctuating, constant, light speed, instantaneous speed. This limit

A. K. Gupta

1999-01-01

215

A Hierarchical Analysis Approach for High Performance Computing and Communication Applications  

Microsoft Academic Search

The proliferation of high performance computers and high -speed networks has made parallel and distributed computing feasible and cost-effect ive on High Performance Computing and Communication Systems (HPCC). However, the design, analysis and development of parallel and distributed applications on suc h computing systems are still very challenging tasks. Therefore, there is a great need for an integrated multilevel analysis

Salim Hariri; Pramod K. Varshney; Luying Zhou; Haibo Xu; Shihab Ghaya

1999-01-01

216

Generation of high-energy (>15 MeV) neutrons using short pulse high intensity lasers  

SciTech Connect

A roadmap is suggested and demonstrated experimentally for the production of high-energy (>15 MeV) neutrons using short pulse lasers. Investigation with a 3D Monte Carlo model has been employed to quantify the production of energetic neutrons. Numerical simulations have been performed for three nuclear reactions, d(d,n){sup 3}He, {sup 7}Li(d,n){sup 8}Be, and {sup 7}Li(p,n){sup 7}Be, driven by monoenergetic ion beams. Quantitative estimates for the driver ion beam energy and number have been made and the neutron spectra and yield in the ion propagation direction have been evaluated for various incident ion energies. In order to generate neutron fluence above a detection limit of 10{sup 6} neutrons/sr, either {approx}10{sup 10} protons with energy 20-30 MeV or comparable amount of deuterons with energy 5-10 MeV are required. Experimental verification of the concept with deuterons driven by the Titan laser (peak intensity 2 Multiplication-Sign 10{sup 19} W/cm{sup 2}, pulse duration of 9 ps, wavelength 1.05 {mu}m, and energy of 360 J) is provided with the generation of neutrons with energy of up to 18 MeV from {sup 7}Li(d,n){sup 8}Be reactions. Future research will focus on optimized schemes for ion acceleration for production of high-energy neutrons, which will involve efficient target design, laser parameter optimization, and converter material.

Petrov, G. M.; Davis, J.; Petrova, Tz. B. [Naval Research Laboratory, Plasma Physics Division, 4555 Overlook Ave. SW, Washington, DC 20375 (United States); Higginson, D. P. [Mechanical and Aerospace Engineering, University of California-San Diego, La Jolla, California 92093 (United States); Lawrence Livermore National Laboratory, Livermore, California 94440 (United States); McNaney, J. M. [Lawrence Livermore National Laboratory, Livermore, California 94440 (United States); McGuffey, C.; Qiao, B.; Beg, F. N. [Mechanical and Aerospace Engineering, University of California-San Diego, La Jolla, California 92093 (United States)

2012-09-15

217

High-rate multiuser communications in shallow water.  

PubMed

Passive multiuser communications in shallow water previously was demonstrated in the 3-4 kHz band using a time reversal approach. This paper extends those experimental results in three respects. First, a larger bandwidth at higher frequency (11-19 kHz) is employed allowing for the use of various symbol rates (or bandwidths). Second, two different shaping pulses are examined: a raised cosine filter and LFM (linear frequency modulation) chirp. Third, the adaptive time reversal approach with spatial nulling is applied to suppress the crosstalk among users. It is shown that the use of a larger bandwidth is beneficial along with the time reversal receiver which can handle significant intersymbol interference with minimal computational complexity. In addition, adding each user degrades the performance by about 4 dB for the benefit of linear increase in data rate. It is demonstrated that an aggregate data rate of 60 kbits/s can be achieved with a 7.5 kHz bandwidth (a spectral efficiency of 8 bits/s?Hz) by three users distributed over 4.2-m depth at a 2.2 km range in shallow water using 16-QAM (quadrature amplitude modulation). PMID:21110587

Song, H C; Kim, J S; Hodgkiss, W S; Kuperman, W A; Stevenson, M

2010-11-01

218

On-line Admission Control and Circuit Routing for High Performance Computing and Communication  

Microsoft Academic Search

This paper considers the problems of admission control and virtual circuit routing in high performance com- puting and communication systems. Admission con- trol and virtual circuit routing problems arise in nu- merous applications, including video-servers, real-time database servers, and the provision of permanent vir- tual channels in large-scale communications networks. The paper describes both upper and lower bounds on the

Baruch Awerbuch; Rainer Gawlick; Frank Thomson Leighton; Yuval Rabani

1994-01-01

219

Control System With High-Speed and Real-Time Communication Links  

Microsoft Academic Search

Recent technological advances have enabled distributed control systems to be implemented via networks. This allows feedback control loops to be closed over communication channels. This paper develops a control system with high-speed and real-time communication links. Two-degrees-of-freedom control is utilized in this servo control system, and sigma-delta modulation is employed to compress data and to transmit the signal over the

Tianjian Li; Yasutaka Fujimoto

2008-01-01

220

VERY HIGH-SPEED DRILL STRING COMMUNICATIONS NETWORK  

SciTech Connect

Testing of a high-speed digital data transmission system for drill pipe is described. Passive transmission of digital data through 1000 ft of telemetry drill pipe has been successfully achieved. Data rates of up to 2 Mbit/sec have been tested through the 1000 ft system with very low occurrence of data errors: required error correction effort is very low or nonexistent. Further design modifications have been made to improve manufacturability and high pressure robustness of the transmission line components. Failure mechanisms of previous designs at high pressure and high temperature are described. Present design limitations include high temperature application.

David S. Pixton

2002-11-01

221

Path loss modeling and performance trade-off study for short-range non-line-of-sight ultraviolet communications.  

PubMed

We consider outdoor non-line-of-sight deep ultraviolet (UV) solar blind communications at ranges up to 100 m, with different transmitter and receiver geometries. We propose an empirical channel path loss model, and fit the model based on extensive measurements. We observe range-dependent power decay with a power exponent that varies from 0.4 to 2.4 with varying geometry. We compare with the single scattering model, and show that the single scattering assumption leads to a model that is not accurate for small apex angles. Our model is then used to study fundamental communication system performance trade-offs among transmitted optical power, range, link geometry, data rate, and bit error rate. Both weak and strong solar background radiation scenarios are considered to bound detection performance. These results provide guidelines to system design. PMID:19259234

Chen, Gang; Xu, Zhengyuan; Ding, Haipeng; Sadler, Brian

2009-03-01

222

High Speed and Mobility - Communications in the Fast Lane?  

Microsoft Academic Search

The growing interest in distributed computing and computer networking in general on the one hand and advances in telecommunica tion services on the other hand have given rise to considerable R&D efforts in the area of high speed networking. The ATM (Asynchronous Transfer Mode) technology which will be used to realize the future Broadband-ISDN offers the capabilities to integrate high

O. Spaniol; A. Fasbender; S. Hoff; R. Karabek

1996-01-01

223

Implementation of a 20Mbps high-speed base-band processing unit with synchronisation: A communications test-bed  

Microsoft Academic Search

The high demand in providing broadband mobile services for 3G+ systems motivates researchers and engineers to design, implement and test highly efficient and scalable high speed communication systems. With similar motivations, in this paper, we present a high speed base-band processing unit implemented in software targeting high speed hardware devices for advanced communication receiver design. The hardware platform, implementation methodologies,

Sithamparanathan Kandeepan; Bijan Rohani; Manora Caldera

2007-01-01

224

The research of high-speed clock in space laser communication  

NASA Astrophysics Data System (ADS)

Space laser communication is moving in a wider bandwidth, greater distances, is more accurate and more narrow laser communication beam direction, faster bandwidth as well as communication interface chip high-speed clock more demanding requirements of the low frequency noise, and good reliability, small size and low power consumption characteristics. Production of ADI's ADF4350 integrated voltage-controlled oscillator (VCO) bandwidth frequency synthesizer just to meet this requirement clock frequency This paper describes the basic principles and operating characteristics of the broadband frequency synthesizer. In this paper we use CPLD to control the ADF4350 and give a control electric circuit with CPLD structure and based on Verilog program. Simulation and experimental results show that the lock-in effect is good, easy to control, and reliable performance. It is able to generate stable clock, suitable for applications in laser communication.

Yang, Hong-kun; Tong, Shou-feng; Zhang, Lei; Wang, Hao-zeng

2013-08-01

225

High energy, short pulse fiber laser front end for kiloJoule class CPA systems  

Microsoft Academic Search

We are developing an all fiber laser system optimized for providing input pulses for short pulse (1-10ps), high energy (~1kJ) glass laser systems. Fiber lasers are ideal solutions for these systems as they are highly reliable and enable long term stable operation. The design requirements for this application are very different than those commonly seen in fiber lasers. High-energy lasers

J. W. Dawson; S. Mitchell; R. J. Beach; M. J. Messerly; C. W. Siders; H. Phan; C. P. J. Barty

2006-01-01

226

RAPID COMMUNICATION BIOLOGICAL PERCHLORATE REDUCTION IN HIGH-SALINITY SOLUTIONS  

Microsoft Academic Search

Perchlorate (ClO4 ? ) has been detected in numerous ground and surface waters, and has recently been added to the drinking water Candidate Contaminant List in the United States. Perchlorate can be removed from drinking water using ion exchange, but this results in the production of highly saline (7-12%) perchlorate-contaminated brines. Perchlorate-degrading microbial enrichments capable of growth in highly saline

BRUCE E. LOGAN; JUN WU; RICHARD F. UNZ

2001-01-01

227

High-speed magneto-optic switch for optical communication  

Microsoft Academic Search

In this paper, an all fiber high-speed magneto-optic switch based on Faraday rotation in Bismuth-substituted Rare-earth Iron Garnet single crystal is proposed and investigated. It contains optical route, picosecond pulse generator and high-speed magnetic field structure. The optical route is designed with the function of switching the output optical signals in the networks. The biasing circuit for the magnetic field

Jianjian Ruan; Zihua Weng; Shaohan Lin

2009-01-01

228

Short communication High speed injection of radiographic contrast media induces severe particulate contamination  

Microsoft Academic Search

In a study of exogenous particulate contamination during angiography, the effect of injection speed of four kinds of radiographic contrast media (RCM) was investigated. The particle count (¢10 mm) in all RCM increased in a speed-dependent manner and the increase was especially dramatic at 3 ml s21. The extent of increase in particulate matter was higher for ioxaglate than for

M HIRAKAWA; T SENDO; Y KATAOKA; R OISHI

229

Optimum multi-layered cell architecture for personal communication systems with high degree of mobility  

Microsoft Academic Search

The paper presents a multi-layer structure for personal communications services (PCS). An evaluation is shown for low and high mobility of PCS in terms of cost economy, capacity and spectrum usage. It is supposed that the service area with 30 km radius is covered by a multiple micro cells in the low mobility plane, while the high-mobility plane employs macro

Keisuke Ogawa; Takeshi Hattori; Hiroshi Yoshida

1994-01-01

230

Report from the field: Communication technology in a New Jersey high school  

Microsoft Academic Search

The High Technology High School utilizes a technologically advanced communication network in order to enrich relations among teachers, students, parents, and administration. Expanded and improved use of telephones, televisions, and computer systems enable individuals essential to the school's operation to work together on a regular basis. The success of new telecommunications networks is evident in their popularity across the nation.

Scott Taylor

1995-01-01

231

Communications Strategies on Alcohol and Highway Safety. Volume II. High School Youth. Final Report.  

ERIC Educational Resources Information Center

|The second part of a two-part, two volume study deals with high school youth and identifies target populations and communications strategies for encouraging personal action steps to prevent drunk driving. Data, collected from interviews and questionnaires, are summarized and presented in tabular form. One fourth of high schoolers in a…

Grey Advertising, Inc., New York, NY.

232

Communicative Spontaneity in Individuals with High Support Needs: An Exploratory Consideration of Causation.  

ERIC Educational Resources Information Center

|Reasons for limited spontaneity of communication in individuals with high support needs are considered and include: it is an inherent characteristic, a product of highly structured teaching programs, a form of learned helplessness, or a product of a failure to systematically program for spontaneity. (Contains references.) (Author/CR)|

Carter, Mark

2002-01-01

233

Developing Students' Literacy Skills Using High-Tech Speech-Generating Augmentative and Alternative Communication Devices  

ERIC Educational Resources Information Center

|This article outlines practical techniques for developing literacy skills in users of high-tech speech-generating augmentative and alternative communication (AAC) devices. The recommended strategies are intended for general classroom teachers who teach literacy skills to students with typical speech. Many students who use high-tech AAC devices…

Wilkins, Julia; Ratajczak, Amy

2009-01-01

234

Short telomeres are frequent in hereditary breast tumors and are associated with high tumor grade.  

PubMed

Telomere shortening is a common event involved in malignant transformation. Critically short telomeres may trigger chromosomal aberrations and produce genomic instability leading to cancer development. Therefore, telomere shortening is a frequent molecular alteration in early stages of many epithelial tumors and in breast cancer correlates with stage and prognosis. A better understanding of the involvement of short telomeres in tumors may have a significant impact on patient management and the design of more specific treatments. To understand the role of telomere length (TL) in breast cancer etiology we measured the length of individual telomere signals in single cells by using quantitative telomere in situ hybridization in paraffin-embedded tissue from hereditary and sporadic breast cancers. A total of 104 tumor tissue samples from 75 familial breast tumors (BRCA1, n = 14; BRCA2, n = 13; non-BRCA1/2, n = 48) and 29 sporadic tumors were analyzed. Assessment of telomere signal intensity allowed estimation of the mean TL and related variables, such as percentage of critically short telomeres and percentage of cells with short telomeres. These data were correlated with the immunohistochemical expression of molecular breast cancer markers. Hereditary BRCA1, BRCA2, and non-BRCA1/2 tumors were characterized by shorter TL comparing to sporadic tumors. Considering all tumors, tumor grade was a strong risk factor determining the proportion of short telomeres or short telomere cells. Moreover, some histopathological features appeared to be differentially associated to hereditary or sporadic subgroups. Short telomeres correlated with ER-negative tumors in sporadic cases but not in familial cases, whereas a high level of apoptosis was associated with shorter telomeres in hereditary BRCA1 and BRCA2 tumors. In addition, TL helped to define a subset of non-BRCA1/2 tumors with short telomeres associated with increased expression of antiapoptotic proteins. These findings highlight the potential interest of TL measurements as markers of aggressiveness in breast cancer. PMID:24036693

Martinez-Delgado, Beatriz; Gallardo, Mercedes; Tanic, Miljana; Yanowsky, Kira; Inglada-Perez, Lucia; Barroso, Alicia; Rodriguez-Pinilla, Maria; Cañamero, Marta; Blasco, Maria A; Benitez, Javier

2013-09-15

235

2 GHz outdoor to indoor propagation at high elevation angles for mobile communications served by high altitude platform stations  

Microsoft Academic Search

High altitude platform stations have been recently proposed as a new means of providing international mobile communications (IMT-2000). One critical issue that has not been resolved yet is the possibility of providing indoor services. This paper examines the penetration into buildings loss at high elevation angles. Two approaches are followed: An empirical model is presented and evaluated through comparison with

D. I. Axiotis; M. E. Theologou

2002-01-01

236

Parent Involvement in Junior High Schools: A Failure to Communicate  

ERIC Educational Resources Information Center

|Although the nature of parent involvement changes as children get older and varies from family to family, junior high school teachers and the families they serve recognize the value of parent involvement in young adolescents' education. Teachers, parents, and students, however, are often uncertain about how to initiate parent involvement in their…

Halsey, Pamela A.

2005-01-01

237

Shorter communication Evaluation of a short-term group therapy program for children with behavior problems and their parents  

Microsoft Academic Search

The current study investigated the effectiveness of a short-term, cognitive behavioral program for 106 primary school-aged children referred with externalizing behavior problems and their parents, compared with 39 children and their parents on a waiting-list to be treated. Exploring Together1 comprised a children's group (anger management, problem-solving and social skills training), a parents' group (parenting skills training and dealing with

Sheryl A. Hemphill; Lyn Littlefield

238

Skeletal Muscle Metabolism of Sea-Level Natives Following Short-Term High-Altitude Residence.  

National Technical Information Service (NTIS)

The influence of short-term high-altitude (HA) residence on intramuscular pH and skeletal muscle enzyme activity of sea-level (SL) residents was investigated. Vastus lateralis muscle samples were obtained by biopsy from rested subjects (n-5) at SL (50M) a...

A. J. Young W. J. Evans E. C. Fisher R. L. Sharp D. L. Costill

1984-01-01

239

Advances in high-power short-pulse fiber laser systems and technology  

Microsoft Academic Search

We review recent advances in Yb fiber lasers and amplifiers for high power short pulse systems. We go on to describe associated recent developments in fiber components for use in such systems. Examples include microstructured optical fibers for pulse compression and supercontinuum generation, and advanced fiber grating technology for chirped-pulse amplifier systems.

J. H. V. Price; A. Malinowski; A. Piper; F. He; W. Belardi; T. M. Monro; M. Ibsen; B. C. Thomsen; Y. Jeong; C. Codemard; M. A. F. Roelens; P. Dupriez; J. K. Sahu; J. Nilsson; D. J. Richardson

2005-01-01

240

Validation of the Short Form of the Career Development Inventory with an Iranian High School Sample  

ERIC Educational Resources Information Center

|A short 33-item form of the Career Development Inventory was validated on a sample of 310 Iranian high school students. Factor analysis indicated that attitude and cognitive subscale items loaded on their respective factors, and that internal reliability coefficients at all levels were satisfactory to good. Support for validity was demonstrated…

Sadeghi, Ahmad; Baghban, Iran; Bahrami, Fatemeh; Ahmadi, Ahmad; Creed, Peter

2011-01-01

241

The Use of Short-Story in Teaching English to the Students of Public High Schools  

ERIC Educational Resources Information Center

Although the studies on the use of literature in teaching English have been increasing abroad, in our country, particularly in public high schools, only English grammar is being taught. The students who are expected to memorise these rules cannot use English. The aim of this study is to exhibit why and how short-story can be used in order to teach…

Eren, Zerrin

2004-01-01

242

Historical Short Stories and the Nature of Science in a High School Biology Class  

Microsoft Academic Search

To overcome students' misconceptions regarding the nature of science, it is essential that teachers utilize instructional activities that accurately and explicitly portray the nature of science within the context of the science content being taught. This study examines the impact of implementing two historical short stories in a high school biology course during units on genetics and biological evolution. The

Jennifer Ann Reid Smith

2010-01-01

243

Automated Control and Monitoring of Thermal Processing Using High Temperature, Short Time Pasteurization  

Microsoft Academic Search

High temperature, short time pasteurization was used to evaluate a computer-based system for con- trolling the pasteurization process, acquiring data, and monitoring records. Software was used for the control of hot water temperature, flow rate through the centrifugal timing pump, and diversion of under- processed product. Three types of control strategies were conducted: single loop, cascade, and multivaria- ble. The

J. E. Schlesser; D. J. Armstrong; A. Cinar; P. Ramanauskas; A. Negiz

1997-01-01

244

Novel method for fabrication of high-efficiency optics for short wavelength radiation  

Microsoft Academic Search

Extreme ultraviolet lithography (EUVL) is the most likely next generation lithography technique which uses radiation near 13.4 nm wavelength. At this short wavelength, most materials readily absorb the radiation, making refractive lens optical systems unusable. We demonstrate a novel method for fabrication of highly efficient optics for extreme ultraviolet (EUV) radiation using focused ion beam (FIB). These optics are based

Rashi Garg; James Evertsen; Gregory Denbeaux

2006-01-01

245

Short-Backfire Antenna as an Element for High-Gain Arrays.  

National Technical Information Service (NTIS)

The short backfire (SBF) antenna consisting of a large reflector illuminated by a dipole feed and smaller disk reflector produces a gain of 15 dB above isotropic. As an array element it has been effciently adapted for various configurations of high-gain a...

H. W. Ehrenspeck J. A. Strom

1971-01-01

246

VERY HIGH-SPEED DRILL STRING COMMUNICATIONS NETWORK  

SciTech Connect

Testing of recent upgrades to the drill pipe telemetry system in a 1000-ft vertical well has shown that the new system can achieve at least 1,000 ft passive transmission distance with sufficient bandwidth to accommodate a digital transmission rate of 2 Mbit/sec. Digitized data from a module at the bottom of the well has been successfully transmitted through the transmission line to the top of the well for a period of approximately one month. Manufacture of 30 prototype range 2 drill pipes has demonstrated greater simplicity of manufacturing and greater consistency of electrical characteristics from part to part, as compared to the first production run previously reported. Further work is needed to improve the high pressure capability of the system and to improve the robustness of the system in a high-vibration environment.

David S. Pixton

2002-08-01

247

Polarization Mode Dispersion in High-Speed Optical Communication Systems  

Microsoft Academic Search

We review the research progress concerning some fundamental issues related to polarization-mode dispersion (PMD) in high-speed fiber-optic transmission systems. We pay particular attention to issues such as the PMD-induced pulse broadening, PMD measurement and emulation, as well as PMD compensation. An electrical equalization technique based on a transversal filter and an optical technique based on a nonlinear chirped fiber Bragg

M. F. FERREIRA; A. N. PINTO; P. S. ANDRÉ; N. J. MUGA; J. E. MACHADO; R. N. NOGUEIRA; S. V. LATAS; M. H. SOUSA; J. F. ROCHA

2005-01-01

248

FAST TRACK COMMUNICATION High rate straining of tantalum and copper  

NASA Astrophysics Data System (ADS)

High strain rate measurements reported recently for several tantalum and copper crystal/polycrystal materials are shown to follow dislocation mechanics-based constitutive relations, first at lower strain rates, for dislocation velocity control of the imposed plastic deformations and, then at higher rates, transitioning to nano-scale dislocation generation control by twinning or slip. For copper, there is the possibility of added-on slip dislocation displacements to be accounted for from the newly generated dislocations.

Armstrong, R. W.; Zerilli, F. J.

2010-12-01

249

The Effect of Communication Inhibition on Small Group Interaction.  

ERIC Educational Resources Information Center

|This study examined the effects of high and low communication inhibition on small group interaction. Communication inhibition was identified in terms of a scale developed through the factor analysis of the Personal Report of Confidence as a Speaker--Short Form, the Personal Report of Communication Apprehension--College, and Unwillingness to…

Fenton, Raymond Joseph

250

High-speed electrophoretic separation of DNA fragments using a short capillary.  

PubMed

Capillary electrophoresis using a replaceable gel buffer was applied to the separation of DNA fragments. A short effective length capillary (1-2 cm) at low electric field allowed the separation of a 20-1000 bp ladder in 1 min. Although similar separation speed was achieved with a longer capillary at high field, the resolution of larger fragments was degraded. The short effective length capillaries were able to separate the wildtype and mutant PCR products of the TGF-beta1 gene in under 45 s. PMID:9271135

Chan, K C; Muschik, G M; Issaq, H J

1997-07-18

251

Wavelength engineering of surface-emitting lasers for high-capacity short-reach systems  

Microsoft Academic Search

In this paper, we present the wavelength engineering of surface emitting lasers for use in high speed short reach systems, which may include the wavelength expansion, the wavelength integration and the wavelength stabilization based on fully monolithic VCSEL technologies. We have developed highly strained GaInAs\\/GaAs QW VCSELs emitting at 1.1-1.2 µm band and GaInNAs\\/GaAs VCSELs at 1.3 µm wavelength. Excellent

Fumio Koyama

2003-01-01

252

High resolution X-ray tomography of short fatigue crack nucleation in austempered ductile cast iron  

Microsoft Academic Search

High-resolution X-ray tomography with synchrotron radiation has been used to obtain observations of the early stages of fatigue crack nucleation in an austempered ductile cast iron. The stable short cracks nucleated in the stress concentration of a pore and arrested due to microstructure barriers. These observations demonstrate the potential for future applications of high-resolution tomography to fracture mechanisms research.

T. J. Marrow; J.-Y. Buffiere; P. J. Withers; G. Johnson; D. Engelberg

2004-01-01

253

High-Resolution Simulations of Plasma Interactions with UltraShort Electromagnetic Pulses  

Microsoft Academic Search

Summary form only given. We report results from two types of high-resolution particle-in-cell (PIC) simulations: (i) wake-driven electron acceleration by intense ultra short laser pulses, and (ii) generation of high-power electromagnetic radiation by free-electron laser (FEL) amplifiers. Large-scale full PIC simulations play a crucial role in the modeling of electronic devices, laser-plasma interactions and magnetic reconnection. Inadequate spatial resolution of

Y. A. Omelchenko; H. Karimabadi; J. L. Vay; A. Friedman

2007-01-01

254

Analytical performance study of solar blind non-line-of-sight ultraviolet short-range communication links.  

PubMed

Motivated by recent advances in solid-state incoherent ultraviolet sources and solar blind detectors, we study communication link performance over a range of less than 1 km with a bit error rate (BER) below 10(-3) in solar blind non-line-of-sight situation. The widely adopted yet complex single scattering channel model is significantly simplified by means of a closed-form expression for tractable analysis. Path loss is given as a function of transceiver geometry as well as atmospheric scattering and attenuation and is compared with experimental data for model validation. The BER performance of a shot-noise-limited receiver under this channel model is demonstrated. PMID:18709113

Xu, Zhengyuan; Ding, Haipeng; Sadler, Brian M; Chen, Gang

2008-08-15

255

Designing and implementing Multibeam Smart Antennas for high bandwidth UAV communications using FPGAs  

NASA Astrophysics Data System (ADS)

Requirements for high bandwidth UAV communications are often necessary in order to move large amounts of mission information to/from Users in real-time. The focus of this paper is antenna beamforming for point-to-point, high bandwidth UAV communications in order to optimize transmit and receive power and support high data throughput communications. Specifically, this paper looks at the design and implementation of Multibeam Smart Antennas to implement antenna beamforming in an aerospace communications environment. The Smart Antenna is contrasted against Fast Fourier Transform (FFT) based beamforming in order to quantify the increase in both computational load and FPGA resources required for multibeam adaptive signal processing in the Smart Antenna. The paper begins with an overall discussion of Smart Antenna design and general beamforming issues in high bandwidth communications. Important design considerations such as processing complexity in a constrained Size, Weight and Power (SWaP) environment are discussed. The focus of the paper is with respect to design and implementation of digital beamforming wideband communications waveforms using FPGAs. A Multibeam Time Delay element is introduced based on Lagrange Interpolation. Design data for Multibeam Smart Antennas in FPGAs is provided in the paper as well as reference circuits for implementation. Finally, an example Multibeam Smart Antenna design is provided based on a Xilinx Virtex-7 FPGA. The Multibeam Smart Antenna example design illustrates the concepts discussed in the paper and provides design insight into Multibeam Smart Antenna implementation from the point of view of implementation complexity, required hardware, and overall system performance gain.

Porcello, J. C.

256

Coherent DWDM technology for high speed optical communications  

NASA Astrophysics Data System (ADS)

The introduction of coherent digital optical transmission enables a new generation of high speed optical data transport and fiber impairment mitigation. An initial implementation of 40 Gb/s coherent systems using Dual Polarization Quadrature Phase Shift Keying (DP-QPSK) is already being installed in carrier networks. New systems running at 100 Gb/s DP-QPSK data rate are in development and early technology lab and field trial phase. Significant investment in the 100 Gb/s ecosystem (optical components, ASICs, transponders and systems) bodes well for commercial application in 2012 and beyond. Following in the footsteps of other telecommunications fields such as wireless and DSL, we can expect coherent optical transmission to evolve from QPSK to higher order modulations schemes such as Mary PSK and/or QAM. This will be an interesting area of research in coming years and poses significant challenges in terms of electro-optic, DSP, ADC/DAC design and fiber nonlinearity mitigation to reach practical implementation ready for real network deployments.

Saunders, Ross

2011-10-01

257

Reliability evaluation models for high-reliability & long-life and high-reliability & short-life products  

Microsoft Academic Search

Based on research in reference literatures, this paper classifies the failure modes further and deduces theoretical reliability models for the high-reliability long-life and high- reliability short-life, which are significant in theory. The conventional analysis methods for building reliability models are based on the hypothesis that two states, namely normal and abnormal, are existing in every component of a product without

Guocai Liu

2011-01-01

258

Communication about Contraception and Knowledge of Oral Contraceptives amongst Norwegian High School Students.  

ERIC Educational Resources Information Center

Examines communication about contraception and specific knowledge of oral contraceptives (OCs) in a sample of Norwegian high school students. More females than males discussed contraception at least monthly. Discussions were predominantly held with peers and not adults. Females were far more knowledgeable about OCs than males. The most significant…

Hansen, Thomas; Skjeldestad, Finn Egil

2003-01-01

259

The constitution and characteristics of 20 GHz band high power transmitter for communications satellite  

Microsoft Academic Search

The paper describes the design and characteristics of two 20 GHz band high-power transmitters onboard a communication satellite. The type A transmitter is a lightweight model noted for its electrical performance, while the type B transmitter is an environmental test model designed to withstand severe launching and geostationary orbit conditions. Both transmitters consist of active and standby TWT amplifiers, single

M. Nakamura; F. Kawashima; A. Iso

1975-01-01

260

Valuing a high-tech growth company: the case of EchoStar Communications Corporation  

Microsoft Academic Search

This article uses real options to value a high-tech company with significant growth option potential. The case of EchoStar Communications Corporation is used as an illustration. The company's growth opportunities are modeled and valued as a portfolio of growth options, namely options to expand its pay television, equipment, and internet services. Expansion of the main business can occur geographically (in

Lenos Trigeorgis; Sophocles Ioulianou

2012-01-01

261

Incorporating Historic Knowledge into a Communication Library for Self-Optimizing High Performance Computing Applications  

Microsoft Academic Search

Emerging computing systems have a wide variety of hardware and software components influencing the performance of parallel applications, presenting end-users with a (nearly) unique execution environment on each parallel machine. One of the big challenges of High Performance Computing is therefore to develop portable and efficient codes for any execution environment. The Abstract Data and Communication Library (ADCL) is a

Saber Feki; Edgar Gabriel

2008-01-01

262

Supporting students’ transition from primary school to high school using the Internet as a communication tool  

Microsoft Academic Search

This paper reports on a transition project where the Internet as a communication tool was used to facilitate interactions between primary school and high school students. The qualitative case study involved capturing the online interactions of the students and teachers as well as the use of questionnaires. Results of the study demonstrate that the use of the Internet allowed participants

Damian Maher

2010-01-01

263

EMERGING AIR QUALITY MODELING TECHNOLOGY FOR HIGH PERFORMANCE COMPUTING AND COMMUNICATION ENVIRONMENTS  

EPA Science Inventory

To demonstrate applications of the HPCC technologies in air quality models, we organized the Specialty Evening Session 1, "Emerging Air Quality Modeling Technologies for High Performance Computing and Communication Environment" as a part of the Twenty First NATO/CCMS Internationa...

264

Data Communication Analysis and Algorithm for the Efficiency of Data Distribution in High Performance Computing  

Microsoft Academic Search

To alleviate the data transfer communication cost among the processor elements, many of the hardware interconnects enable data transfer to be performed at the same time as computation. The assignment of tasks to processors problem is well known to be NP-complete except in a few special cases. To improve the overall performance of high performance computing (HPC), this paper develops

Jinchuan Ke; Ming T. Jiang

2008-01-01

265

Optimizing and Modeling Topology Design in High-Speed Optical Wireless Communication Networks  

Microsoft Academic Search

As an affordable alternative solution for the broadband first\\/last mile access, optical wireless communication (OWC) has recently attracted attention from the literature. Among the primary advantages of OWC system are the high data rate, unlicensed spectrum of operation, quick and inexpensive setup. However, the link and bandwidth availability due to interferences from weather or others remain as challenge for designing

Xiaojun Cao

2008-01-01

266

Efficient layering for high speed communication: the MPI over Fast Messages (FM) experience  

Microsoft Academic Search

We describe our experience of designing, implementing, and evaluating two generations of high performance communication libraries, Fast Messages (FM) for Myrinet. In FM 1, we designed a simple interface and provided guarantees of reliable and in-order delivery, and flow control. While this was a significant improvement over previous systems, it was not enough. Layering MPI atop FM 1 showed that

Mario Lauria; Scott Pakin; Andrew A. Chien

1999-01-01

267

High-Efficiency 20 GHz Traveling Wave Tube Development for Space Communications.  

National Technical Information Service (NTIS)

A 75 watt CW high efficiency helix TWT operating at 20 GHz was developed for satellite communication systems. The purpose was to extend the performance capabilities of helix TWTs by using recent technology developments. The TWT described is a unique desig...

S. L. Aldana R. N. Tamashiro

1991-01-01

268

Directions and issues in high performance computing and communications: LLNL's response  

Microsoft Academic Search

This abstract consists of reformatted slides from the talk with a small amount of added connective tissue. First we outline important research areas in High Performance Computing and Communication (HPCC) with an overview of current LLNL work in each area, and then we discuss in more detail some of LLNL's evolving views on massively parallel computing.

Dick Watson

1994-01-01

269

Recent advances in millimeter-wave photonic wireless links for very high data rate communication  

NASA Astrophysics Data System (ADS)

To provide integrated and high quality broadband services, higher carrier frequencies are required in wireless communications. Currently, there is a great deal of interests in wireless communications at sub-terahertz or terahertz frequencies, i.e., the millimeter-wave (MMW) or sub-millimeter-wave (sub-MMW). In this work, we will discuss our recent advances in millimeter-wave photonic wireless links for high data rate (10 - 20 Gb/s) communications. The concept of fiber-to-the-antenna (FTTA) system using radio-over-fiber (ROF) technologies will be given in the introduction. Then a design and the structure of the high speed MMW photonic transmitter, namely near-ballistic unitraveling- carrier photodiode (NBUTC-PD), will be discussed in section 2. In section 3, the operation principle of photonic mm-wave waveform generator (PMWG), which is used to produce the optical pulse train for the photonic transmitter at the antenna-site will be illustrated. We then demonstrate the use of the NBUTC-PD and the PMWG for the downstream and upstream high data rate communications in the W-band.

Pan, C.-L.; Chow, C. W.; Yeh, C. H.; Huang, C. B.; Shi, J. W.

2011-11-01

270

Conflicts and Communication between High-Achieving Chinese American Adolescents and Their Parents  

ERIC Educational Resources Information Center

|Drawing on in-depth interview data collected on 18 high-achieving Chinese American students, the authors examine domains of acculturation-based conflicts, parent and child internal conflicts, and conflict resolution in their families. Their analyses show that well-established negative communication patterns in educational expectations, divergent…

Qin, Desiree Baolian; Chang, Tzu-Fen; Han, Eun-Jin; Chee, Grace

2012-01-01

271

Communication about Contraception and Knowledge of Oral Contraceptives amongst Norwegian High School Students.  

ERIC Educational Resources Information Center

|Examines communication about contraception and specific knowledge of oral contraceptives (OCs) in a sample of Norwegian high school students. More females than males discussed contraception at least monthly. Discussions were predominantly held with peers and not adults. Females were far more knowledgeable about OCs than males. The most…

Hansen, Thomas; Skjeldestad, Finn Egil

2003-01-01

272

The high performance computing and communications (HPCC) program: technologies for the national information infrastructure  

Microsoft Academic Search

The Federal HPCC Program is a 10-agency billion dollar per year effort to accelerate the development of high performance computing and communications technologies and the diffusion of these technologies to improve U.S. competitiveness and the well-being of citizens.

Donald A. B. Lindberg; John C. Toole; Paul R. Young; John S. Cavallini; Lee B. Holcomb; Richard J. Linn Jr.; George R. Cotter; Helen M. Wood; Joan H. Novak; Alexis T. Poliakoff

1994-01-01

273

The High Performance Computing and Communication (HPCC) Program (panel): technologies for the National Information Infrastructure  

Microsoft Academic Search

The Federal HPCC program is a 10-agency billion dollar per year effort to accelerate the development of high performance computing and communications technologies and the diffusion of these technologies to improve U.S. competitiveness and the well-being of citizens.

Donald A. B. Lindberg; John C. Toole; Paul R. Young; John S. Cavallini; Lee B. Holcomb; R. J. Linn; George R. Cotter; Helen M. Wood; Joan H. Novak; Alexis T. Poliakoff

1994-01-01

274

A new multi-slot and multi-level coding technique for high capacity communication system  

Microsoft Academic Search

A new multi-slot and multi-level coding technique for high capacity communication system, known as Multi Slot Amplitude Coding (MSAC) is presented. This technique offers better flexibility in terms of defining the symbol based on time slot and signal level in order to generate more unique symbols as a line code with better clock information since all the symbols have zero

R. Talib; M. F. L. Abdullah; A. Malekmohammadi; M. K. Abdullah

2010-01-01

275

Social networks, information and communication technologies, and high school youths' civic and political role- identities  

Microsoft Academic Search

This study investigates how the structures and dynamics of social relationships and information and communication technologies shape high school youths' civic and political role-identities. Structural symbolic interactionism, a framework that looks at what societal and social psychological aspects define individuals' roles and shape individuals' actions, is applied as a framework to unravel processes that may mediate adolescents' civic and political

Peyina Lin

276

System and method that suppresses intensity fluctuations for free space high-speed optical communication  

Microsoft Academic Search

A high-speed (Gbps), free space optical communication system is based on spectral encoding of radiation from a wide band light source, such as a laser. By using partially coherent laser beams in combination with a relatively slow photosensor, scintillations can be suppressed by orders of magnitude for distances of more than 10 km. To suppress the intensity fluctuations due to

Gennady P. Berman; Alan R. Bishop; Dinh C. Nguyen; Boris M. Chernobrod; Vacheslav N. Gorshkov

2009-01-01

277

Two Decades of U. S. Army Mobile High-Frequency Communications  

Microsoft Academic Search

This paper is an historical account of the trend in development of U. S. Army high-frequency mobile radio communications of medium power in the period 1940 to 1960. Starting with one of the first really mobile sets of this power level, in a wide variety of installation configurations to meet World War II requirements, it relates the progressive fulfillment of

H. C. Hawkins

1960-01-01

278

Whole-genome sequencing and assembly with high-throughput, short-read technologies.  

PubMed

While recently developed short-read sequencing technologies may dramatically reduce the sequencing cost and eventually achieve the $1000 goal for re-sequencing, their limitations prevent the de novo sequencing of eukaryotic genomes with the standard shotgun sequencing protocol. We present SHRAP (SHort Read Assembly Protocol), a sequencing protocol and assembly methodology that utilizes high-throughput short-read technologies. We describe a variation on hierarchical sequencing with two crucial differences: (1) we select a clone library from the genome randomly rather than as a tiling path and (2) we sample clones from the genome at high coverage and reads from the clones at low coverage. We assume that 200 bp read lengths with a 1% error rate and inexpensive random fragment cloning on whole mammalian genomes is feasible. Our assembly methodology is based on first ordering the clones and subsequently performing read assembly in three stages: (1) local assemblies of regions significantly smaller than a clone size, (2) clone-sized assemblies of the results of stage 1, and (3) chromosome-sized assemblies. By aggressively localizing the assembly problem during the first stage, our method succeeds in assembling short, unpaired reads sampled from repetitive genomes. We tested our assembler using simulated reads from D. melanogaster and human chromosomes 1, 11, and 21, and produced assemblies with large sets of contiguous sequence and a misassembly rate comparable to other draft assemblies. Tested on D. melanogaster and the entire human genome, our clone-ordering method produces accurate maps, thereby localizing fragment assembly and enabling the parallelization of the subsequent steps of our pipeline. Thus, we have demonstrated that truly inexpensive de novo sequencing of mammalian genomes will soon be possible with high-throughput, short-read technologies using our methodology. PMID:17534434

Sundquist, Andreas; Ronaghi, Mostafa; Tang, Haixu; Pevzner, Pavel; Batzoglou, Serafim

2007-05-30

279

The Influence of High and Low-Context Communication Styles On the Design, Content, and Language of Business-To-Business Web Sites  

Microsoft Academic Search

Language and communication, especially high- versus low-context communication styles, have been shown to lead to differences in Web sites. Low-context communication provides the lowest common denominator for intercultural communication through the Internet by making messages linear, articulated, explicit, and therefore easier to understand in the absence of contextual clues. Based on theories of intercultural business communication and recent empirical studies,

Jean-Claude Usunier; Nicolas Roulin

2010-01-01

280

High-Capacity Quantum Secure Direct Communication Based on Quantum Hyperdense Coding with Hyperentanglement  

NASA Astrophysics Data System (ADS)

We present a quantum hyperdense coding protocol with hyperentanglement in polarization and spatial-mode degrees of freedom of photons first and then give the details for a quantum secure direct communication (QSDC) protocol based on this quantum hyperdense coding protocol. This QSDC protocol has the advantage of having a higher capacity than the quantum communication protocols with a qubit system. Compared with the QSDC protocol based on superdense coding with d-dimensional systems, this QSDC protocol is more feasible as the preparation of a high-dimension quantum system is more difficult than that of a two-level quantum system at present.

Wang, Tie-Jun; Li, Tao; Du, Fang-Fang; Deng, Fu-Guo

2011-04-01

281

Public key suppression and recovery using a PANDA ring resonator for high security communication  

NASA Astrophysics Data System (ADS)

An interesting security technique that uses the dark-bright soliton conversion control within the microring resonator is proposed. The obtained outputs for a dark-bright soliton dynamic state can be controlled and used to form the public key suppression for communication security application. However, a good design should be possible to be fabricated; therefore, by using the parameters based on the practical device parameters, the simulation results obtained have shown that the proposed system can indeed be achieved. The public key suppression and public key recovery can be used in a highly secure communication system and has potential applications in optical cryptography.

Juleang, Pakorn; Phongsanam, Prapas; Mitatha, Somsak; Yupapin, Preecha P.

2011-03-01

282

Design/Drafting (Graphic Communications). Industrial Arts, Senior High--Level II. North Dakota Senior High Industrial Arts Curriculum Guides.  

ERIC Educational Resources Information Center

|This course guide for a design/drafting course is one of four developed for the graphic communications area in the North Dakota senior high industrial arts education program. (Eight other guides are available for two other areas of Industrial Arts--energy/power and production.) Part 1 provides such introductory information as a definition and…

Poehls, Eddie; And Others

283

A rejoinder to "Exercise Programs for Patients with Post-Polio Syndrome: a case report"--a short communication.  

PubMed

This communication is in response to the article by Michael T Gross and Charles P Schuch entitled "Exercise Programs for Patients with Post-Polio Syndrome: A Case Report" published in the January 1989 issue of Physical Therapy. The investigators examined the effects of a rigorous isokinetic training program on peak torque of the knee flexor and extensor muscles of a post-polio patient. The literature on post-polio syndrome, however, does not support the use of either conventional muscle strengthening regimens or rigorous isokinetic exercise programs in the management of post-polio syndrome. In addition, based on the observation that there was no appreciable increase in muscle strength in either the affected or the apparently unaffected leg, the investigators concluded that their rigorous exercise program was not deleterious. The lack of a normal training response, however, is consistent with bilateral muscle fatigue secondary to overuse rather than muscle weakness secondary to disuse. This result is consistent with the need for a balance between rest and low-intensity exercise, which will help to maintain or enhance function while slowing rather than hastening further deterioration. We hope that this rejoinder clarifies some of the misconceptions that may arise from the Gross and Schuch article and that physical therapists consider very carefully the rationale for any type of exercise program for post-polio patients. PMID:2748723

Dean, E; Ross, J; MacIntyre, D

1989-08-01

284

Thermal analysis method of high capacity communications satellite with heat pipes  

NASA Astrophysics Data System (ADS)

Thermal analysis method for heat pipe embedded communications equipment panel is treated in this paper. The main problem of the thermal analysis is how to construct the mathematical model under the limitation of computer CPU memory size. The mathematical model for the heat pipe embedded panel is first established based on the experiments. The essence of this method is to divide panel area into several small regions and perform thermal analysis independently using the fact of low thermal conductivity of honeycomb sandwich panel. To check the correctness of this method, the experiment using the test panel which thermally simulates the north communications equipment panel of two-ton class high capacity communications satellite has been conducted. The experiment shows the method works well.

Tsunoda, Hiroaki; Nakajima, Katsuhiko; Miyasaka, Akihiro

285

The road to the United Nations High Level Meeting on chronic non-communicable diseases.  

PubMed

The United Nations High Level Meeting (UNHLM) on non-communicable diseases (NCDs) will take place in New York on September 19 and 20, 2011. This historic event will focus world attention on the chronic non-communicable diseases (CNCDs) for the first time. In 2008, CNCDs, principally cardiovascular disease, cancer; chronic lung diseases and diabetes, accounted for 63% (or 36 million) of the 57 million deaths occurring worldwide. Many of these deaths may be considered premature (involving 9.1 million persons aged less than 60 years), and around 80% of overall deaths occurred in low and middle income countries. Chronic non-communicable diseases are therefore a major cause of premature death, with resulting enormous negative impact on national economies and global development, while continuing to increase at worrying rates particularly in the developing world. Without successful interventions, NCD-related deaths are projected to reach 52 million by 2030. PMID:22097667

Hassell, T; Hennis, A

2011-07-01

286

MICROMACHINING OF GLASS WITH SHORT NS-PULSES AND HIGHLY REPETITIVE FS LASER PULSES  

Microsoft Academic Search

In this paper first results on 3d laser cutting of glasses as a technology for rapid tooling, obtained at the laser institute of the University of Applied Sciences Mitt- weida, are presented. The investigations were carried out with a short pulse Nd:YVO4 slab laser from Edge- wave (Aachen) and a high repetition rate femtosecond laser of Clark-MXR Inc. Michigan. In

U. Loeschner; S. Mauersberger; R. Ebert; H. Exner; J. Schille; P. Regenfuss; L. Hartwig

287

Skeletal muscle metabolism of sea-level natives following short-term high-altitude residence  

Microsoft Academic Search

Summary  The influence of short-term high-altitude (HA) residence on intramuscular pH and skeletal muscle enzyme activity of sea-level (SL) residents was investigated. Vastus lateralis muscle samples were obtained by biopsy from rested subjects (n=5) at SL (50 m) and on the 18th day of HA residence (4,300 m) for determination of glycogen phosphorylase, hexokinase, malate dehydrogenase, and total lactate dehydrogenase activities.

A. J. Young; W. J. Evans; E. C. Fisher; R. L. Sharp; D. L. Costill; J. T. Maher

1984-01-01

288

Use of shorted coaxial transmission line for high-power microwave measurement  

Microsoft Academic Search

In order to reduce the effective area of the receiving antenna to receive microwave power in the high electric field regions, a 1.76 GHz shorted coaxial transmission line (SCTL) is investigated numerically and experimentally in this paper. When the frequency is 1.76 GHz, the simulation results show that the general gain and the effective area of the SCTL are -10.21

Yu-Wei Fan; Hui-Huang Zhong; Ting Shu; Zhi-Qiang Li; Heng Zhou; Wei-Hong Zhou; Ling Luo

2009-01-01

289

Fundamental mechanisms of optical damage in short-wavelength high-power lasers  

Microsoft Academic Search

Evidence has been accumulating for many years that the physical mechanisms responsible for damage to optical materials in and from high-power, short-wave-length lasers (SWLs) differ in fundamental ways from the thermal processes identified in infrared and visible-wavelength laser damage problems. We propose that this difference stems primarily from the electronic nature of the absorption and excitation processes which occur when

R. F. Haglund Jr.; N. H. Tolk; G. W. York

1985-01-01

290

Highly-charged heavy-ion production with short pulse lasers  

Microsoft Academic Search

This MathCAD document describes a possible approach using a PW -class short pulse laser to form a useful number (10¹²) of high and uniform charge state ions with low ion temperature (<< 100 eV) and low momentum spread (δp{sub z}\\/p, < 10⁻⁴ ) for injection into heavy-ion fusion accelerators. As a specific example, we consider here Xenon{sup +26}, which has

G. Logan; T. Bitmire; M. Perry; O. Anderson; T. Kuehl

1998-01-01

291

High-Efficiency operation of PWM inverter-driven hysteresis motor with short-duration overexcitation  

Microsoft Academic Search

This paper presents the new scheme for high-efficiency operation of PWM inverter-driven hysteresis motor with short-duration overexcitation. When the terminal voltage Vi of the hysteresis motor running at synchronous speed is continuously increased up to nVi (n>1) and then continuously decreased to Vi, input currents are reduced and output power is increased at the same time. Because of this, the

Tomotsugu Kubota; Takahiro Tamura; Kazumi Kurihara

2009-01-01

292

Modeling Alkaline Phosphatase Inactivation in Bovine Milk During High-Temperature Short-Time Pasteurization  

Microsoft Academic Search

Alkaline phosphatase (AP) is used as the indicator enzyme for proper pasteurization of bovine milk. Predictive modeling of AP inactivation during high-temperature short-time (HTST) pasteurization would support regulations; thus ensuring the safety of heat treated milk. Activation energy (Ea) of AP in milk was measured experimentally using the capillary tube method, and Ea was found to be 429252 J\\/mol. The

Q. Lu; P. Piyasena; G. S. Mittal

2001-01-01

293

An enhanced GaAs monolithic transimpedance amplifier for low noise and high speed optical communications  

Microsoft Academic Search

The design, implementation and test results of a simple GaAs monolithic transimpedance amplifier with enhanced performance for high-speed optical communications are described. A cascode configuration, improved in terms of bandwidth and noise, is used. On-wafer and on-carrier measurements show close agreement with simulated behavior. Excellent performance with high transimpedance gain, a bandwidth from DC to 1.6 GHz, low noise, and

J. A. Casao; P. Dorta; J. L. Caceres; M. Salazar-Palma; J. Perez

1992-01-01

294

Social-Communicative Abilities in Young High-Risk Preterm Children  

Microsoft Academic Search

The social-communicative abilities of a high-risk preterm (n=25) and a full-term group (n=19) were assessed at the age of two, using a standardized observation schedule (ADOS-G; Lord et al., 1999). The preterm children could be described as “high risk” in terms of their low gestational age and\\/or severe neonatal problems. They had significantly higher scores than their full-term peers, indicating less

Isabel De Groote; Herbert Roeyers; Petra Warreyn

2006-01-01

295

Developing Students' Literacy Skills Using High-Tech Speech-Generating Augmentative and Alternative Communication Devices  

Microsoft Academic Search

This article outlines practical techniques for developing literacy skills in users of high-tech speech-generating augmentative and alternative communication (AAC) devices. The recommended strategies are intended for general classroom teachers who teach literacy skills to students with typical speech. Many students who use high-tech AAC devices participate in grade-level instruction. Strategies based on the National Reading Panel's research-based findings for effective

Julia Wilkins; Amy Ratajczak

2009-01-01

296

An overview of LLNL high-energy short-pulse technology for advanced radiography of laser fusion experiments  

Microsoft Academic Search

The technical challenges and motivations for high-energy, short-pulse generation with NIF and possibly other large-scale Nd : glass lasers are reviewed. High-energy short-pulse generation (multi-kilojoule, picosecond pulses) will be possible via the adaptation of chirped pulse amplification laser techniques on NIF. Development of metre-scale, high-efficiency, high-damage-threshold final optics is a key technical challenge. In addition, deployment of high energy petawatt

C. P. J. Barty; J. Britten; R. Beach; G. Beer; C. Brown; S. Bryan; J. Caird; T. Carlson; J. Crane; J. Dawson; A. C. Erlandson; D. Fittinghoff; M. Hermann; C. Hoaglan; A. Iyer; L. Jones II; I. Jovanovic; A. Komashko; O. Landen; Z. Liao; W. Molander; S. Mitchell; E. Moses; N. Nielsen; H.-H. Nguyen; J. Nissen; S. Payne; D. Pennington; L. Risinger; M. Rushford; K. Skulina; M. Spaeth; B. Stuart; G. Tietbohl; B. Wattellier

2004-01-01

297

High-order statistical equalizer for nonlinearity compensation in dispersion-managed coherent optical communications.  

PubMed

Fiber nonlinearity has become a major limiting factor to realize ultra-high-speed optical communications. We propose a fractionally-spaced equalizer which exploits a trained high-order statistics to deal with data-pattern dependent nonlinear impairments in fiber-optic communications. The computer simulation reveals that the proposed 3-tap equalizer improves Q-factor by more than 2 dB for long-haul transmissions of 5,230 km distance and 40 Gbps data rate. We also demonstrate that the joint use of a digital backpropagation (DBP) and the proposed equalizer offers an additional 1-2 dB performance improvement due to the channel shortening gain. A performance in high-speed transmissions of 100 Gbps and beyond is evaluated as well. PMID:22772267

Koike-Akino, Toshiaki; Duan, Chunjie; Parsons, Kieran; Kojima, Keisuke; Yoshida, Tsuyoshi; Sugihara, Takashi; Mizuochi, Takashi

2012-07-01

298

High-purity isotope production by short-term HFIR irradiations  

Microsoft Academic Search

Techniques and procedures have been developed at the transuranium processing plant to produce quantities of special high-purity isotopes, e.g. ²²⁷Ac, ²⁴²Cm, ²⁵°Cf, ²⁵¹Cf, and ²⁵⁴Cf by short-term irradiation of appropriate target materials in the high flux isotope reactor (HFIR). The general sequences of operations required to produce special isotopes includes (a) purification of the target isotope from other actinides, lanthanides,

J. B. Jr. Knauer; C. W. Alexander; J. E. Bigelow; J. T. Wiggins

1987-01-01

299

Short Communication Prediction of trace compounds in biogas from anaerobic digestion using the MATLAB Neural Network Toolbox  

Microsoft Academic Search

The outlook to apply the highly energetic biogas from anaerobic digestion into fuel cells will result in a significantly higher electrical efficiency and can contribute to an increase of renewable energy production. The practical bottleneck is the fuel cell poisoning caused by several gaseous trace compounds like hydrogen sulfide and ammonia. Hence artificial neural networks were developed to predict these

Alexander M. Domnanovich; Loredana Zani; Rudolf Braun; Peter Holubar

300

Short Communication Correlation between serum levels of interleukin- 4 and alexithymia scores in healthy female subjects: preliminary findings  

Microsoft Academic Search

Objective: Some studies suggest that inaccuracy in recognizing and describing emotional states, combined with a highly descriptive mode of expression, as in alexithymia, may influ- ence the immune response. We therefore investigated in healthy women the relationship between alexithymia and circulating levels of IL-1, IL-2 and IL-4. Method: Seventeen mentally and physically healthy women aged between 20 and 25 years

Maurice Corcos; Olivier Guilbaud; Sabrina Paterniti; Florence Curt; Linnea Hjalmarsson; Marlene Moussa; Jean Chambry; Philippe Jeammet

301

The High-Performance Computing and Communications program, the national information infrastructure and health care.  

PubMed Central

The High-Performance Computing and Communications (HPCC) program is a multiagency federal effort to advance the state of computing and communications and to provide the technologic platform on which the National Information Infrastructure (NII) can be built. The HPCC program supports the development of high-speed computers, high-speed telecommunications, related software and algorithms, education and training, and information infrastructure technology and applications. The vision of the NII is to extend access to high-performance computing and communications to virtually every U.S. citizen so that the technology can be used to improve the civil infrastructure, lifelong learning, energy management, health care, etc. Development of the NII will require resolution of complex economic and social issues, including information privacy. Health-related applications supported under the HPCC program and NII initiatives include connection of health care institutions to the Internet; enhanced access to gene sequence data; the "Visible Human" Project; and test-bed projects in telemedicine, electronic patient records, shared informatics tool development, and image systems.

Lindberg, D A; Humphreys, B L

1995-01-01

302

High-energy K? radiography using high-intensity, short-pulse lasers  

NASA Astrophysics Data System (ADS)

The characteristics of 22-40 keV K? x-ray sources are measured. These high-energy sources are produced by 100 TW and petawatt high-intensity lasers and will be used to develop and implement workable radiography solutions to probe high-Z and dense materials for the high-energy density experiments. The measurements show that the K? source size from a simple foil target is larger than 60 ?m, too large for most radiography applications. The total K? yield is independent of target thicknesses, verifying that refluxing plays a major role in photon generation. Smaller radiating volumes emit brighter K? radiation. One-dimensional radiography experiments using small-edge-on foils resolved 10 ?m features with high contrast. Experiments were performed to test a variety of small volume two-dimensional point sources such as cones, wires, and embedded wires, measured photon yields, and compared the measurements with predictions from hybrid-particle-in-cell simulations. In addition to high-energy, high-resolution backlighters, future experiments will also need imaging detectors and diagnostic tools that are workable in the high-energy range. An initial look at some of these detector issues is also presented.

Park, H.-S.; Chambers, D. M.; Chung, H.-K.; Clarke, R. J.; Eagleton, R.; Giraldez, E.; Goldsack, T.; Heathcote, R.; Izumi, N.; Key, M. H.; King, J. A.; Koch, J. A.; Landen, O. L.; Nikroo, A.; Patel, P. K.; Price, D. F.; Remington, B. A.; Robey, H. F.; Snavely, R. A.; Steinman, D. A.; Stephens, R. B.; Stoeckl, C.; Storm, M.; Tabak, M.; Theobald, W.; Town, R. P. J.; Wickersham, J. E.; Zhang, B. B.

2006-05-01

303

Short communication The geometry of the Iapetus Suture Zone in central Ireland deduced from a magnetotelluric study  

Microsoft Academic Search

The crustal geometry of the Iapetus Suture Zone (ISZ) in central Ireland is inferred from an electrical resistivity model derived from broadband and long period magnetotelluric measurements along a 200-km-long NNW-SSE profile. The model highlights an undulating high conductivity layer of thickness 10-15 km and resistivity 2-5 m, at middle to lower crustal depths interpreted as sulphide-bearing graphitic sediments deposited

C. K. Rao; Alan G. Jones; Max Moorkamp

304

Short communication Technique to measure CO2 mixing ratio in small flasks with a bellows\\/IRGA system  

Microsoft Academic Search

We developed a laboratory method to obtain high precision CO2 mixing ratios in air samples contained in 100 ml glass flasks, which involves extracting air from the flask into a pre-evacuated manifold containing a variable-volume metal bellows. Compressed air from the bellows is then routed to a non-dispersive infrared gas analyzer (IRGA). Tests indicate that this configuration has an overall

D. R. Bowling; C. S. Cook; J. R. Ehleringer

2001-01-01

305

Short Communication Feline infectious peritonitis virus-infected monocytes internalize viral membrane-bound proteins upon antibody addition  

Microsoft Academic Search

Feline infectious peritonitis virus (FIPV) may cause a highly lethal infection in cats, in spite of a usually strong humoral immune response. Antibodies seem unable to identify infected cells and mediate antibody-dependent cell lysis. In this study, the effect of antibodies on Feline coronavirus (FCoV)-infected monocytes was investigated. Upon addition of FCoV-specific antibodies, surface-expressed viral proteins were internalized through a

Hannah L. Dewerchin; Els Cornelissen; Hans J. Nauwynck

306

The initial freezing point temperature of beef rises with the rise in pH: a short communication.  

PubMed

This study tested the hypothesis that the initial freezing point temperature of meat is affected by pH. Sixty four bovine M. longissimus thoracis et lumborum were classified into two ultimate pH groups: low (<5.8) and high pH (>6.2) and their cooling and freezing point temperatures were determined. The initial freezing temperatures for beef ranged from -0.9 to -1.5°C (?=0.6°C) with the higher and lower temperatures associated with high and low ultimate pH respectively. There was a significant correlation (r=+0.73, P<0.01) between beef pH and freezing point temperature in the present study. The outcome of this study has implications for the meat industry where evidence of freezing (ice formation) in a shipment as a result of high pH meat could result in a container load of valuable chilled product being downgraded to a lower value frozen product. PMID:23410892

Farouk, M M; Kemp, R M; Cartwright, S; North, M

2013-01-11

307

ScalaTrace: Scalable Compression and Replay of Communication Traces for High Performance Computing  

SciTech Connect

Characterizing the communication behavior of large-scale applications is a difficult and costly task due to code/system complexity and long execution times. While many tools to study this behavior have been developed, these approaches either aggregate information in a lossy way through high-level statistics or produce huge trace files that are hard to handle. We contribute an approach that provides orders of magnitude smaller, if not near-constant size, communication traces regardless of the number of nodes while preserving structural information. We introduce intra- and inter-node compression techniques of MPI events that are capable of extracting an application's communication structure. We further present a replay mechanism for the traces generated by our approach and discuss results of our implementation for BlueGene/L. Given this novel capability, we discuss its impact on communication tuning and beyond. To the best of our knowledge, such a concise representation of MPI traces in a scalable manner combined with deterministic MPI call replay are without any precedent.

Noeth, M; Ratn, P; Mueller, F; Schulz, M; de Supinski, B R

2008-05-16

308

High power broadcasting skywave transmitters interference analysis for navigation and communication systems  

NASA Astrophysics Data System (ADS)

The operation of high-power broadcasting transmitters (Tx) can strongly interfere with collocated and even remote radio communication and navigation systems on broad frequency ranges. In these cases, extensive analysis and computation method developments are essential in order to assess the feasibility of reliable operation of indispensable radio communication links. The magnitudes of the interference effects are computed, based on specifications of 500-kW skywave Tx parameters and the important airborne VHF radio navigation and communication systems. The critical interference (i.e., desensitization or blocking of the victim airborne receivers) and other interference modes are analyzed using semiempirical state-of-the-art computation methods. Limits for victim receiver distances and frequency intervals for no-interference situations and optimal reception conditions are obtained. The semiempirical method developed includes the analysis of the influential system parameters when one or more 500-kW Tx are operating simultaneously. The computation and measurement results are compared and discussed. It is concluded that the most crucial VHF/VOR communication/navigation system will be only slightly disturbed, with a loss of sensitivity of less than 6 dB in the desensitization interference mode from a 500-kW HF Tx, if proper front-end preselector BPFs are used. The effect of the interfering Tx harmonics which fall in the VOR frequency is more disturbing to the investigated navigation system.

Gavan, J.; Joffe, Elya B.

1990-03-01

309

Feasibility of optical wireless communication link using high-brightness illumination LEDs  

NASA Astrophysics Data System (ADS)

The feasibility of optical wireless communication link using high-brightness illumination light-emitting diodes (LEDs) is reported. The eye patterns of single-color red, green, and blue LEDs are measured and compared. For the blue LED, the 3 dB bandwidth is measured. An optical transmitter module incorporates seven LEDs as a basic building block for planar light and a packaged silicon photodiode is used as a receiver. From the experimental demonstration with the 7-LED transmitter and a receiver, it is shown that the optical wireless communication link using high-brightness illumination LEDs can perform 10 Mb/s data transmission without any optimized optical filter to enhance optical gain.

Lee, Chung G.; Park, Chul S.; Kim, Jung-Hun; Kim, Dong-Hwan

2006-05-01

310

Performance analysis of high altitude platform multi-hop optical communication with non-regenerative system  

NASA Astrophysics Data System (ADS)

Based on non-regenerative relays, the bit error probability expressions of CSI-assisted relay and fixed-gain relays for high altitude platform multi-hop optical communication is given. The effect of the factors, including atmospheric turbulence pointing error and relay node position, on the performance of multi-hop optical links is analyzed. The simulation results show that the influence of atmospheric turbulence on optical links is greater than that of pointing error. The improvement of average SNR per hop and transmit power on multi-hop optical communications may be restricted by pointing error. Compared to CSI-assisted relay, fixed-gain relay is suited to more hops links with the condition of high average SNR per hop.

Wang, Xiang; Zhao, Shang-hong; Shi, Lei; Li, Yong-jun; Zheng, Guang-wei; Zhao, Gu-hao; Zhu, Zi-hang

2013-08-01

311

Aluminium K-Shell High-Resolution Spectroscopy of Short and Long Scale Length Plasmas  

SciTech Connect

Highly ionized aluminium plasmas created using long (nanosecond) and short (picosecond) duration laser pulses are studied using a combination of high resolution X-ray spectroscopy and computational modeling tools. The experiments are designed to be simple and the emission spectra well characterized so that detailed observation of strong, single frequency electric fields effects can be observed and studied. Strong oscillating electric fields can modify the emission spectra of ions by altering spectral line shapes, through ionization processes, and the appearance of field-induced satellite lines. However, field-induced effects are expected to be weak, thus high dispersion, high luminosity spatially resolving spectrometers are employed. Initial results are discussed and an example of a possible field induced modification of a spectral line shape is presented.

Woolsey, N. C.; Chambers, D. M.; Courtois, C.; Gregory, C. D.; Hall, I. M.; Howe, J. [Department of Physics, University of York, York, Y010 5DD (United Kingdom); Foerster, E.; Uschmann, I. [Institute of Optics and Quantum Electronics, University of Jena, 07743 Jena (Germany); Renner, O. [Institute of Physics, Academy of Sciences CR, Prague (Czech Republic)

2006-04-07

312

Short communication: expression of transporters and metabolizing enzymes in the female lower genital tract: implications for microbicide research.  

PubMed

Abstract Topical vaginal microbicides have been considered a promising option for preventing the male-to-female sexual transmission of HIV; however, clinical trials to date have not clearly demonstrated robust and reproducible effectiveness results. While multiple approaches may help enhance product effectiveness observed in clinical trials, increasing the drug exposure in lower genital tract tissues is a compelling option, given the difficulty in achieving sufficient drug exposure and positive correlation between tissue exposure and microbicide efficacy. Since many microbicide drug candidates are substrates of transporters and/or metabolizing enzymes, there is emerging interest in improving microbicide exposure and efficacy through local modulation of transporters and enzymes in the female lower genital tract. However, no systematic information on transporter/enzyme expression is available for ectocervical and vaginal tissues of premenopausal women, the genital sites most relevant to microbicide drug delivery. The current study utilized reverse transcriptase polymerase chain reaction (RT-PCR) to examine the mRNA expression profile of 22 transporters and 19 metabolizing enzymes in premenopausal normal human ectocervix and vagina. Efflux and uptake transporters important for antiretroviral drugs, such as P-gp, BCRP, OCT2, and ENT1, were found to be moderately or highly expressed in the lower genital tract as compared to liver. Among the metabolizing enzymes examined, most CYP isoforms were not detected while a number of UGTs such as UGT1A1 were highly expressed. Moderate to high expression of select transporters and enzymes was also observed in mouse cervix and vagina. The implications of this information on microbicide research is also discussed, including microbicide pharmacokinetics, the utilization of the mouse model in microbicide screening, as well as the in vivo functional studies of cervicovaginal transporters and enzymes. PMID:23607746

Zhou, Tian; Hu, Minlu; Cost, Marilyn; Poloyac, Samuel; Rohan, Lisa

2013-05-17

313

Lifetime measurements of high-lying short lived states in {sup 69}As  

SciTech Connect

Lifetimes of high-spin states in {sup 69}As have been measured using Doppler shift attenuation technique with the GASP and RFD setup. The determined transition probabilities indicate large deformation associated with some rotational bands in this nucleus.

Matejska-Minda, M.; Bednarczyk, P.; Fornal, B.; Ciemala, M.; Kmiecik, M.; Krzysiek, M.; Maj, A.; Meczynski, W.; Myalski, S.; Styczen, J.; Zieblinski, M.; Angelis, G. de; Huyuk, T.; Michelagnoli, C.; Sahin, E.; Aydin, S.; Farnea, E.; Menegazzo, R.; Recchia, F.; Ur, C. A. [Institute of Nuclear Physics, Polish Academy of Sciences, Krakow (Poland); INFN, Laboratori Nazionali di Legnaro, Legnaro (Italy); Dipartimento di Fisica e INFN Padova (Italy); Dipartimento di Fisica e INFN Milano (Italy); Heavy Ion Laboratory, University of Warsaw (Poland); University of York (United Kingdom); and others

2012-10-20

314

Effects of Mass Communication on Attitudes toward Anabolic Steroids: An Analysis of High School Seniors  

Microsoft Academic Search

Drawing on a national probability sample of high school seniors (n = 2,560), this research explores relationships between exposure to four types of mass communication—magazines, movies, newspapers, and television—and attitudes toward anabolic steroids, operationalized along three dependent measures. Logistic regression analyses revealed statistically significant relationships among (a) magazine exposure and estimates of drug use in professional sports, (b) newspaper and

Bryan E. Denham

2006-01-01

315

A flexible and high performance cellular mobile communications system based on Orthogonal Multi-Carrier SSMA  

Microsoft Academic Search

The conventional Direct-Sequence Spread-Spectrum-Multiple-Access (DS-SSMA) system with RAKE-receiver is an interesting approach in mobile communications in order to combat the frequency selectivity of the channel. The main advantages of DS-SSMA are well known, but its capacity is limited by other-user interference. Another interesting SSMA technique that combats the frequency selectivity of the channel and achieves high spectral efficiency is based

K. Fazel; S. Kaiser; M. Schnell

1995-01-01

316

Base station placement for in-building mobile communication systems to yield high capacity and efficiency  

Microsoft Academic Search

A study is made of the problem of placing base stations to yield high capacity and efficiency in an in-building direct-sequence code-division multiple-access wireless communication system. A key requirement for solving this problem is a reliable but simple model of in-building propagation. A number of propagation models are considered as part of a system's performance analysis and are found to

Keith S. Butterworth; Kevin W. Sowerby; Allan G. Williamson

2000-01-01

317

Design and implementation of high-speed communication modem using ultrasonic sensors for underwater sensor networks  

Microsoft Academic Search

Underwater sensor networks (USN) for ocean development and disaster prevention have been emerged as one of interesting research topics recently. Since low-power, high-speed and inexpensive communication modem is a prerequisite for deployment of USN, in this paper we design and implement an underwater modem by utilizing general-purpose waterproof ultrasonic sensors. Also, we make some experiments in a water tank containing

Moo-Kwang Byeon; Bo-Won Kim; Jun-Ho Jeon; Sung-Joon Park

2008-01-01

318

Methods of Test Waveform Synthesis for High-Speed Data Communication Devices  

Microsoft Academic Search

When testing ISDN (integrated services digital network) and other high-data-rate communications devices, stimulus waveforms will often emulate signals that a device under test (DUT) will process in its final application. When conventionally architected digital-signal-processor-based instrumentation is used to provide these waveforms, there exist test conditions which can easily overburden machine capabilities. The author explores an instrument architecture in use, based

Kenneth Lanier

1989-01-01

319

Design and Evaluation of an Adaptive Communication System for High Peformance Distributed Computing Applications  

Microsoft Academic Search

The ability to access a wide range of computing systems through global high speed networks such as Internet2 and vBNS will accelerate the development of network-centric applications and services. These applications and services, in general, have a wide range of quality of service requirements that must be provided by the underlying computing and communications infrastructure. However, the current com- munication

Sung-yong Park; Salim Hariri; Ilkyeun Ra

2000-01-01

320

Efficient layering for high speed communication: the MPI over Fast Messages (FM) experience  

Microsoft Academic Search

We describe our experience of designing, implementing, and evaluating two generations of high performance communication libraries,\\u000a Fast Messages (FM) for Myrinet. In FM 1, we designed a simple interface and provided guarantees of reliable and in-order delivery,\\u000a and flow control. While this was a significant improvement over previous systems, it was not enough. Layering MPI atop FM\\u000a 1 showed that

Mario Lauria; Scott Pakin; Andrew Chien

1999-01-01

321

A 60 GHz Radio-Over-Fiber Network Architecture for Seamless Communication With High Mobility  

Microsoft Academic Search

We demonstrate a 60 GHz broadband picocellular Radio-over-Fiber network architecture that enables seamless connectivity for highly mobile end-users. Its seamless communication capabilities arise by the supported handover scheme that relies on a novel Moving Extended Cell (MEC) concept. MEC exploits user-centric virtual groups of adjacent cells that transmit the same data content to the user and utilizes a switch mechanism

Nikos Pleros; Konstantinos Vyrsokinos; Kostas Tsagkaris; Nikolaos D. Tselikas

2009-01-01

322

Using J-DSP to introduce communications and multuviedia technologies to high schools  

Microsoft Academic Search

Abstract - This paper describes interactive Java software and,modular ,web ,content ,developed ,at Arizona State University aimed at introducing elements of digital signal processing (DSP), multimedia, and communications technologies to high school (HS) students. The,effort is motivated,by several ,needs ,and ,trends ,that include: initiatives for graduating technology-aware HS students, the need to attract HS students from diverse backgrounds,to engineering programs,

Andreas Spanias; Thrassos Thrasyvoulou; Yu Song; Constantinos Panayiotou

2003-01-01

323

Short communication: estimation of genetic parameters for residual feed intake and feeding behavior traits in dairy heifers.  

PubMed

Data from a 2-yr feeding trial of Holstein-Friesian heifers (n=842) were used to examine the heritability of feeding behavior traits and their relationships with residual feed intake (RFI), a measure of feed efficiency. Five traits were assessed: number of meals, feeding duration, dry matter intake (DMI), eating rate, and average meal size. For estimating genetic parameters, all traits were simultaneously fitted in a multivariate model with a genomic relationship matrix calculated from heifers' high-density genotype data. All 5 traits were moderately heritable (0.45-0.50), which was slightly higher than the estimate for RFI (0.40 ± 0.09). Two traits had modest genetic correlations with RFI (DMI and feeding duration; 0.45 ± 0.13 and 0.27 ± 0.15, respectively), and 2 traits had modest phenotypic correlations with RFI (DMI and eating rate; 0.52 ± 0.03 and 0.23 ± 0.04, respectively). The results indicate that feeding behavior (1) may differ between efficient and inefficient animals and (2) may be useful for selecting animals with better feed efficiency. However, the limitation is that measurements on DMI are still essential. It is therefore possible that a more efficient selection tool for RFI may be the use of high-density DNA markers to make direct genomic predictions for RFI. PMID:23462165

Lin, Z; Macleod, I; Pryce, J E

2013-02-22

324

Short communication: An assessment of the use of malaria rapid tests by village health volunteers in rural Laos.  

PubMed

Rapid malaria diagnosis, a key component of malaria control strategies, is hampered by the expense and training requirements of reliable microscopy. Rapid malaria antigen tests may improve the diagnosis of malaria in the rural tropics. After 1 h training 64 village health volunteers (VHVs) from rural Laos, with no previous laboratory experience, performed two malaria rapid diagnostic tests (ParacheckPf and OptiMAL) accurately. The reliability of six VHVs was assessed longitudinally, over 10 months with different frequencies of retraining. Compared with microscopy, error rates in dipstick interpretation were low (<2%) for both tests and were not associated with retraining frequency (P>0.2). Previously untrained Lao VHVs performed malaria rapid tests reliably with high sensitivity and specificity after minimal training. PMID:14996360

Mayxay, Mayfong; Newton, Paul N; Yeung, Shunmay; Pongvongsa, Tiengkham; Phompida, Samlane; Phetsouvanh, Rattanaxay; White, Nicholas J

2004-03-01

325

High Energy K(alpha) Radiography Using High-intensity, Short-pulse Lasers  

SciTech Connect

We have performed experiments using Callisto, the Vulcan 100 TW and the Vulcan Petawatt high intensity lasers to understand the characteristics of high energy, K{alpha} x-ray sources and to implement workable radiography solutions at 20-100 keV. Our measurements show that the K{alpha} size from a simple foil target is larger than 60 {micro}m, far larger than the experiment resolution requirement. The total K{alpha} yield is independent of target thicknesses verifying that refluxing plays a major role in photon generation. Smaller radiating volumes emit brighter K{alpha} radiation. 1-D radiography experiments using small-edge-on foils resolved 10 {micro}m features with high contrast. We tested a variety of small volume 2-D point sources such as cones, wires, and embedded wires, measuring photon yields and comparing our measurements with predictions from hybrid-PIC LSP simulations. In addition to high-energy, high-resolution backlighters, future experiments will also need imaging detectors and diagnostic tools that are workable in the 20-100 keV energy range. An initial look at some of these detector issues is also presented.

Park, H; Izumi, N; Key, M H; King, J A; Koch, J A; Landen, O L; Patel, P K; Price, D F; Remington, B A; Robey, H F; Snavely, R A; Tabak, M; Town, R J; Wickersham, J E; Stoeckl, C; Storm, M; Theobald, W; Chambers, D M; Eagelton, R; Goldsack, T; Clarke, R J; Heathcote, R; Giraldez, E; Nikroo, A; Steinman, D A; Stephens, R B; Zhang, B B

2005-11-16

326

Short communication: Severe symptomatic hyperlactatemia among HIV type 1-infected adults on antiretroviral therapy in Côte d'Ivoire.  

PubMed

Stavudine is no longer recommended for use in first-line antiretroviral therapy (ART), but it remains in high demand worldwide because it is affordable. We report the clinical presentation and incidence of severe hyperlactatemia (SL) in HIV-infected adults who initiated ART between April 2005 and May 2009 in Côte d'Ivoire, West Africa. In a prospective cohort study at the HIV care center affiliated with the National Centre for Blood Transfusion, we used standardized forms to record baseline and follow-up data. We measured serum lactate levels for all adults on ART who showed signs of hyperlactatemia. SL was defined as serum lactate >2.5 mmol/liter. Overall, 806 adults initiated ART. Among the 591 patients (73%) on stavudine-containing regimens, 394 were women (67%); the median pre-ART CD4 count was 150/mm3 and the median body mass index was 20.9 kg/m2. These patients were followed for a median of 28 months. We detected SL only among patients taking stavudine. The incidence of SL was 0.55/100 person-years (PY) (95% CI 0.47-0.63) overall and 0.85/100 PY among women (95% CI 0.75-0.95). Among the eight patients with SL, 100% lost >9% of body weight before diagnosis, 100% had serum lactate >4 mmol/liter (range 4.2-12.1), 50% had pre-ART BMI >25 kg/m2, and three patients died (38%), accounting for 6.4% of deaths among patients taking stavudine. As long as HIV clinicians continue to use stavudine in sub-Saharan Africa, they should watch out for acute unexplained weight loss in patients taking ART, particularly among women and patients with high pre-ART BMI. PMID:20707728

Minga, Albert; Lewden, Charlotte; Dohoun, Lambert; Abo, Yao; Emieme, Arlette; Coulibaly, Ali; Salamon, Roger; Eholié, Serge; Anglaret, Xavier; Danel, Christine

2010-09-01

327

Short Communication: Transmitted Drug Resistance and Molecular Epidemiology in Antiretroviral Naive HIV Type 1-Infected Patients in Rhode Island  

PubMed Central

Abstract Transmission of HIV-1 drug resistance has important clinical and epidemiological consequences including earlier treatment failure and forward transmission of resistance strains in high-risk groups. To evaluate the prevalence and molecular epidemiology of transmitted drug resistance in Rhode Island, we collected genotypic, demographic, clinical, and laboratory data from treatment-naive individuals presenting to the largest outpatient HIV clinic in the state from January 2007 to November 2007. Sequences from 35 treatment-naive individuals were available, 83% of whom were men who had sex with men (MSM). All sequences were HIV-1 subtype B. Drug resistance mutations were identified in 7/35 [20%; 95% confidence interval (CI), 0.08–0.37] patients, six of whom had K103N. Two phylogenetic transmission clusters were found, involving 17% (6/35) of individuals, three in each cluster. We did not find an association between belonging to a cluster and age, gender, AIDS-defining illness, CD4 cell count, or viral load. Drug resistance mutations were more commonly observed in transmission clusters (p?=?0.08). Individuals in one cluster all had K103N and were MSM who had attended local bathhouses. Individuals forming clusters were significantly more likely to have visited a bathhouse compared to nonclusters (p?=?0.02). The prevalence of transmitted drug resistance in Rhode Island is high, further justifying genotypic testing on presentation to care and prior to treatment initiation. Molecular epidemiological analysis and association of resistance with phylogenetic networks using data obtained for clinical purposes may serve as useful tools for the prevention of drug resistance transmission and for contact tracing.

Tashima, Karen; Cartwright, Charles P.; Gillani, Fizza S.; Mintz, Orli; Zeller, Kimberly; Kantor, Rami

2011-01-01

328

Wireless infrared communications  

Microsoft Academic Search

The use of infrared radiation as a medium for high-speed short-range wireless digital communication is discussed. Available infrared links and local-area networks are described. Advantages and drawbacks of the infrared medium are compared to those of radio and microwave media. The physical characteristics of infrared channels using intensity modulation with direct detection (IM\\/DD) are presented including path losses and multipath

JOSEPH M. KAHN; JOHN R. BARRY

1997-01-01

329

A new high intensity and short-pulse molecular beam valve  

NASA Astrophysics Data System (ADS)

In this paper, we report on the design and performance of a new home-built pulsed gas valve, which we refer to as the Nijmegen Pulsed Valve (NPV). The main output characteristics include a short pulse width (as short as 20 ?s) combined with operating rates up to 30 Hz. The operation principle of the NPV is based on the Lorentz force created by a pulsed current passing through an aluminum strip located within a magnetic field, which opens the nozzle periodically. The amplitude of displacement of the opening mechanism is sufficient to allow the use of nozzles with up to 1.0 mm diameter. To investigate the performance of the valve, several characterizations were performed with different experimental methods. First, a fast ionization gauge was used to measure the beam intensity of the free jet emanating from the NPV. We compare free jets from the NPV with those from several other pulsed valves in current use in our laboratory. Results showed that a high intensity and short pulse-length beam could be generated by the new valve. Second, the NPV was tested in combination with a skimmer, where resonance enhanced multiphoton ionization combined with velocity map imaging was used to show that the NPV was able to produce a pulsed molecular beam with short pulse duration (~20 ?s using 0.1% NO/He at 6 bars) and low rotational temperature (~1 K using 0.5% NO/Ar at 6 bars). Third, a novel two-point pump-probe method was employed which we label double delay scan. This method allows a full kinematic characterization of the molecular beam, including accurate speed ratios at different temporal positions. It was found that the speed ratio was maximum (S = 50 using 0.1% NO/He at 3 bars) at the peak position of the molecular beam and decreased when it was on the leading or falling edge.

Yan, B.; Claus, P. F. H.; van Oorschot, B. G. M.; Gerritsen, L.; Eppink, A. T. J. B.; van de Meerakker, S. Y. T.; Parker, D. H.

2013-02-01

330

A new high intensity and short-pulse molecular beam valve.  

PubMed

In this paper, we report on the design and performance of a new home-built pulsed gas valve, which we refer to as the Nijmegen Pulsed Valve (NPV). The main output characteristics include a short pulse width (as short as 20 ?s) combined with operating rates up to 30 Hz. The operation principle of the NPV is based on the Lorentz force created by a pulsed current passing through an aluminum strip located within a magnetic field, which opens the nozzle periodically. The amplitude of displacement of the opening mechanism is sufficient to allow the use of nozzles with up to 1.0 mm diameter. To investigate the performance of the valve, several characterizations were performed with different experimental methods. First, a fast ionization gauge was used to measure the beam intensity of the free jet emanating from the NPV. We compare free jets from the NPV with those from several other pulsed valves in current use in our laboratory. Results showed that a high intensity and short pulse-length beam could be generated by the new valve. Second, the NPV was tested in combination with a skimmer, where resonance enhanced multiphoton ionization combined with velocity map imaging was used to show that the NPV was able to produce a pulsed molecular beam with short pulse duration (~20 ?s using 0.1% NO/He at 6 bars) and low rotational temperature (~1 K using 0.5% NO/Ar at 6 bars). Third, a novel two-point pump-probe method was employed which we label double delay scan. This method allows a full kinematic characterization of the molecular beam, including accurate speed ratios at different temporal positions. It was found that the speed ratio was maximum (S = 50 using 0.1% NO/He at 3 bars) at the peak position of the molecular beam and decreased when it was on the leading or falling edge. PMID:23464190

Yan, B; Claus, P F H; van Oorschot, B G M; Gerritsen, L; Eppink, A T J B; van de Meerakker, S Y T; Parker, D H

2013-02-01

331

High-peak-power short-pulse fiber laser for materials processing  

NASA Astrophysics Data System (ADS)

High-speed, high-resolution materials processing strongly benefits from optical sources that deliver high peak power in short, high-repetition-rate pulses of excellent beam quality. These sources are also of interest for achieving high average power at nonlinearly-generated wavelengths. Until recently, high peak power, high-repetition-rate pulses have only been available from solid-state lasers. Fiber lasers and amplifiers offer significant advantages over solid-state lasers in terms of size and wall-plug efficiency. This paper presents a fiber-based master-oscillator/power-amplifier (MOPA) source at 1064nm featuring 84-?m-core, polarization-maintaining Yb-doped photonic crystal fiber that generates ~20ps - 100ps pulses at variable pulse repetition frequencies (PRFs), from 10kHz to 100MHz. The flexibility in pulse format allows the source to be tailored to the application. Where peak power is critical, the PRF is reduced to achieve maximum peak power. Where average power is needed, the PRF is increased to achieve high average power. Peak powers of ~4MW have been achieved at reduced PRF (100kHz), and average powers greater than 172W have been demonstrated at high PRF (100MHz) in a linearly-polarized output beam.

Thomas, Alison M.; Alterman, Deborah A.; Bowers, Mark S.

2009-02-01

332

[Short communication: Evaluation of the flu vaccine administered to health care workers in Trakya University Hospital in 2006].  

PubMed

After the detection of human cases of highly pathogenic avian influenza A (H5N1) virus in Eastern Turkey in January 2006, Turkish Ministry of Health has had declared "National Plans of Activity for Pandemic Influenza". All health-care facilities were recommended to develop contingency plans. Then the essential activities were started in August 2006 in Trakya University, Faculty of Medicine (Edirne, Trace region of Turkey), and institutional education about pandemic influenza and preventive measures was implemented to health care workers (HCWs). In November 2006, health care workers were offered inactivated flu vaccine (Vaxigrip, Sanofi Pasteur, France) supplied by the Ministry of Health. The aim of this questionary survey was to evaluate the visions and conceptions of health care workers about influenza vaccination during the vaccination campaign. All the participants were informed by using an information form including the indications, contraindications and possible adverse reactions of flu vaccine, and were requested to complete the questionnaire about influenza vaccination according to their own perception before vaccination. Vaccine recipients were also invited to the vaccination unit if they had any adverse reaction. A total of 1041 HCWs (560 female, 481 male; mean age: 32.8 +/- 8.2 years) completed the questionnaire. Of them 884 subjects (85%) have accepted to be vaccinated, while 157 subjects (15%) have not. It was determined that 72 HCWs (6.9%) had been administered flu vaccine in 2005, and 38 (3.7%) have had an underlying chronic disease requiring medical therapy. Six subjects (16%) with an underlying chronic disease were vaccinated in 2005, while 66 HCWs (6.6%) without any chronic disease received vaccination voluntarily. Seven workers (0.7%) declined vaccination as they defined hypersensitivity to egg, and 84 workers (8%) had influenza vaccine voluntarily before the campaign in 2006. Sixty six workers (6.3%) have refused to be vaccinated as they considered influenza vaccination ineffective to protect against flu. Two workers (0.2%) had allergic skin reactions such as erythema and itching after vaccination. It can be concluded that influenza vaccination of the health care workers is a part of infection control policies and it is also a matter of patient safety. The implementation of necessary education programmes and attempts to emphasize the importance of vaccination of health care workers especially dealing with high risk patients, would be of crucial importance to decrease the morbidity and mortality due to influenza infections. PMID:18444572

Kulo?lu, Figen; Celik', Aygül Do?an; Yulu?kural, Zerrin; Erkan, Tülay; Keskin, Serap; Akata, Filiz

2008-01-01

333

The Short Circuit Instability in Protoplanetary Disks: Processing high temperature minerals  

NASA Astrophysics Data System (ADS)

We introduce a magneto-hydrodynamic instability which occurs, among other locations, in the inner, hot regions of protoplanetary disks, and which alters the way in which resistive dissipation of magnetic energy into heat proceeds. This instability can be likened to both an electrical short circuit and lightning, as it concentrates the dissipation of magnetic energy by means of the enhanced release of free electrons. This instability can generate very high temperatures, making it an excellent candidate for thermally processing protoplanetary disk solids, from annealing silicates to melting chondrules or even CAIs.

Hubbard, A.; McNally, C. P.; Mac Low, M. M.; Ebel, D. S.; D'Alessio, P.

2013-04-01

334

Fast-electron transport in high-intensity short-pulse laser - solid experiments  

NASA Astrophysics Data System (ADS)

The interaction of short-pulse 0741-3335/39/5/001/img7 high-intensity 0741-3335/39/5/001/img8 lasers with solid targets generates large numbers of energetic 0741-3335/39/5/001/img9 electrons. The energetic electrons can only penetrate into the solid if the solid can supply an equivalent charge-neutralizing return current. We develop a simple model which shows that in many cases the solid cannot support the required return current and the fast electrons are confined by electric fields to the surface of the target. The target response to laser irradiation depends strongly on the electrical conductivity of the solid.

Bell, A. R.; Davies, J. R.; Guerin, S.; Ruhl, H.

1997-05-01

335

Implementing Molecular Dynamics for Hybrid High Performance Computers - 1. Short Range Forces  

SciTech Connect

The use of accelerators such as general-purpose graphics processing units (GPGPUs) have become popular in scientific computing applications due to their low cost, impressive floating-point capabilities, high memory bandwidth, and low electrical power requirements. Hybrid high performance computers, machines with more than one type of floating-point processor, are now becoming more prevalent due to these advantages. In this work, we discuss several important issues in porting a large molecular dynamics code for use on parallel hybrid machines - 1) choosing a hybrid parallel decomposition that works on central processing units (CPUs) with distributed memory and accelerator cores with shared memory, 2) minimizing the amount of code that must be ported for efficient acceleration, 3) utilizing the available processing power from both many-core CPUs and accelerators, and 4) choosing a programming model for acceleration. We present our solution to each of these issues for short-range force calculation in the molecular dynamics package LAMMPS. We describe algorithms for efficient short range force calculation on hybrid high performance machines. We describe a new approach for dynamic load balancing of work between CPU and accelerator cores. We describe the Geryon library that allows a single code to compile with both CUDA and OpenCL for use on a variety of accelerators. Finally, we present results on a parallel test cluster containing 32 Fermi GPGPUs and 180 CPU cores.

Brown, W Michael [ORNL; Wang, Peng [NVIDIA, Santa Clara, CA; Plimpton, Steven J [ORNL; Tharrington, Arnold N [ORNL

2011-01-01

336

Improvement of short tandem repeat analysis of samples highly contaminated by humic acid.  

PubMed

We investigated several methods for obtaining successful short tandem repeat (STR) results from high-humic acid (HA)-content samples. DNA purification efficiency was tested for QIAquick(®) PCR Purification, QIAamp(®) DNA Investigator and Prepfiler™ Forensic DNA Extraction kits. HA-removal capacity of Inhibitor Remover and InhibitEX(®) Tablet was tested. Experiments on overcoming HA effects on STR amplification were conducted using an AmpliTaq Gold(®) DNA Polymerase and a TaKaRa Ex Taq™ Hot Start Version (Ex Taq HS) with BSA addition. QIAquick kit was most efficient in HA removal and Ex Taq HS showed high resistance to HA. Increasing the amounts of Taq polymerases and BSA addition were shown to be efficient in overcoming PCR inhibition, but BSA addition was superior to the former method. Inhibitor Remover and InhibitEX(®) Tablet did not positively affect the STR results. This study will help achieve better STR results with high-HA-content samples. PMID:24112347

Seo, Seung Bum; Jin, Hong Xuan; Lee, Hye Young; Ge, Jianye; King, Jonathan L; Lyoo, Sung Hee; Shin, Dong Hoon; Lee, Soong Deok

2013-08-28

337

Improving Switching Performance of Power MOSFETs Used in High Rep-Rate, Short Pulse, High-Power Pulsers  

SciTech Connect

As their switching and power handling characteristics improve, solid-state devices are finding new applications in pulsed power. This is particularly true of applications that require fast trains of short duration pulses. High voltage (600-1200V) MOSFETs are especially well suited for use in these systems, as they can switch at significant peak power levels and are easily gated on and off very quickly. MOSFET operation at the shortest pulse durations is not constrained by the intrinsic capabilities of the MOSFET, but rather by the capabilities of the gate drive circuit and the system physical layout. This project sought to improve MOSFET operation in a pulsed power context by addressing these issues. The primary goal of this project is to improve the switching performance of power MOSFETs for use in high rep-rate, short pulse, high-power applications by improving the design of the gate drive circuits and the circuit layouts used in these systems. This requires evaluation of new commercial gate drive circuits and upgrading the designs of LLNL-developed circuits. In addition, these circuits must be tested with the fastest available high-voltage power MOSFETs.

Cook, E G

2006-09-19

338

Characteristics of ion emission from plasma produced by high-energy short-wavelength (438 nm) laser radiation  

Microsoft Academic Search

Efficient production of highly charged (z>45) high-energy (up to ~20 MeV) Ta ions by the interaction of a short-wavelength subnanosecond laser pulse with a solid target has been demonstrated by experimental studies of ion emission from plasma generated by the PALS high-energy short-wavelength (3omega0) iodine laser system (<=0.25 kJ, 0.4 ns, 0.438 mum, <=1016 W cm-2) in Prague. The plasma

J. Wolowski; J. Badziak; F. P. Boody; S. Gammino; H. Hora; K. Jungwirth; J. Krása; L. Láska; P. Parys; M. Pfeifer; K. Rohlena; A. Szydlowski; L. Torrisi; J. Ullschmied; E. Woryna

2003-01-01

339

Development of reprogrammable high frame-rate detector devices for laser communication pointing, acquisition and tracking  

NASA Astrophysics Data System (ADS)

A Two Terminal Laser Communication Test Bed has been developed at The Aerospace Corporation. This paper presents the design and preliminary results of a reprogrammable detector within the Test Bed for use in pointing, acquisition, and tracking between a Satellite-to-Satellite Laser Communication link. The detector may be commanded by an emulated spacecraft Command & Data Handling subsystem to switch between full-array scanning and "small sized" N x M pixel Field of View (FOV) for high-rate laser tracking. The approach follows a parallel path to implement the signal processing algorithm on two different hardware resources: a Field Programmable Gate Array (FPGA) and a Digital Signal Processor (DSP). The focus of this effort is to present a methodology for testing and evaluating various techniques for advanced focal plane array (FPA) hardware, as well as sensor FPA control, image processing and laser beam X & Y position algorithms.

Norton, Terita; Conner, Kenneth; Covington, Richard; Ngo, Hung; Rink, Christine

2008-03-01

340

A high-power Q-band PHEMT for communication terminal applications  

Microsoft Academic Search

A high-power 0.15 ?m gate-length pseudomorphic HEMT (PHEMT), developed specifically for high reliability millimeter-wave satellite communication applications, is reported. The device has demonstrated state-of-the-art performance at 44.5 GHz, generating nearly 800 mW output power with 5.8 dB power gain and 25% power-added efficiency, and is designed for operation at low channel temperatures for excellent long-term reliability. The 1800 ?m gate-width

P. M. Smith; C. T. Creamer; W. F. Kopp; D. W. Ferguson; P. Ho; J. R. Willhite

1994-01-01

341

Method of high speed flow field influence and restrain on laser communication  

NASA Astrophysics Data System (ADS)

For laser communication performance which carried by airplane or airship, due to high-speed platform movement, the air has two influences in platform and laser communication terminal window. The first influence is that aerodynamic effect causes the deformation of the optical window; the second one is that a shock wave and boundary layer would be generated. For subsonic within the aircraft, the boundary layer is the main influence. The presence of a boundary layer could change the air density and the temperature of the optical window, which causes the light deflection and received beam spot flicker. Ultimately, the energy hunting of the beam spot which reaches receiving side increases, so that the error rate increases. In this paper, aerodynamic theory is used in analyzing the influence of the optical window deformation due to high speed air. Aero-optics theory is used to analyze the influence of the boundary layer in laser communication link. Based on this, we focused on working on exploring in aerodynamic and aero-optical effect suppression method in the perspective of the optical window design. Based on planning experimental aircraft types and equipment installation location, we optimized the design parameters of the shape and thickness of the optical window, the shape and size of air-management kit. Finally, deformation of the optical window and air flow distribution were simulated by fluid simulation software in the different mach and different altitude fly condition. The simulation results showed that the optical window can inhibit the aerodynamic influence after optimization. In addition, the boundary layer is smoothed; the turbulence influence is reduced, which meets the requirements of the airborne laser communication.

Meng, Li-xin; Wang, Chun-hui; Qian, Cun-zhu; Wang, Shuo; Zhang, Li-zhong

2013-08-01

342

Survival of Listeria monocytogenes in milk during high-temperature, short-time pasteurization.  

PubMed Central

Milk from cows inoculated with Listeria monocytogenes was pooled for 2 to 4 days and then heated at 71.7 to 73.9 degrees C for 16.4 s or at 76.4 to 77.8 degrees C for 15.4 s in a high-temperature, short-time plate heat exchanger pasteurization unit. L. monocytogenes was isolated from milk after heat treatment in six of nine pasteurization trials done at 71.7 to 73.9 degrees C and in none of three trials done at 76.4 to 77.8 degrees C. An average of 1.5 to 9.2 L. monocytogenes cells was seen in each milk polymorphonuclear leukocyte before heat treatment in 11 of 12 pasteurization trials. Noticeable degradation of leukocytes with intracellular listeria was detected in unpasteurized milk after 3 days of storage at 4 degrees C, and by 4 days of storage leukocytes had deteriorated to cellular debris, suggesting that holding unpasteurized milk refrigerated for 4 or more days would eliminate a protective effect leukocytes may provide for increasing heat resistance of L. monocytogenes. Results indicate that under the conditions of this study, L. monocytogenes can survive the minimum high-temperature, short-time treatment (71.7 degrees C, 15 s) required by the U.S. Food and Drug Administration for pasteurizing milk. Images

Doyle, M P; Glass, K A; Beery, J T; Garcia, G A; Pollard, D J; Schultz, R D

1987-01-01

343

Laser driven proton beam for the applications: toward ultra-high intensity & short pulse proton beam  

NASA Astrophysics Data System (ADS)

As a benchmark experiment to realize a novel and compact laser driven proton accelerator whose significant features are high number density in a short pulse width (~ns), 2.4 MeV laser driven proton beam is stably focused at 1 Hz repetition rate by using a pair of permanent quadrupole magnets (PMQs) with large apertures whose diameters and field strengths are 3.5 cm and 55 T/m for the first and 2.3 cm and 60 T/m for the second magnets, respectively. The proton beam has been focused to a focal spot of 3×8 mm2 in horizontal and vertical direction (full width at half maximum) at 650~mm from the source, which is well reproduced by the simulation. The further optimization of the focusing system will sure to pave a way to the novel proton accelerator with which we can investigate the physics appeared in the short time scale as well as that in a high energy density matter, oncology, astrophysics, and so on.

Nishiuchi, M.; Daido, H.; Daito, I.; Ikegami, M.; Mori, M.; Orimo, S.; Ogura, K.; Sagisaka, A.; Yogo, A.; Pirozhkov, A. S.; Sugiyama, H.; Kiriyama, H.; Okada, H.; Kanazawa, S.; Kondo, S.; Shimomura, T.; Tanoue, M.; Nakai, Y.; Sasao, H.; Wakai, D.; Sakaki, H.; Hori, T.; Bolton, P.; Choi, I. W.; Sung, J. H.; Lee, J.; Oishi, Y.; Fujii, T.; Nemoto, K.; Souda, H.; Noda, A.; Iseki, Y.; Yoshiyuki, T.

2009-07-01

344

High-extinction-ratio micro polarizing beam splitter for short wavelength optical storage applications.  

PubMed

A surface-micromachined high-extinction-ratio polarizing beam splitter (PBS) using low absorptive silicon nitride layers for blue wavelength applications are demonstrated. The micro polarizing beam splitter consists of novel stack of two silicon nitride layers separated by an air gap. A PBS optimization model is established to achieve both high extinction-ratio and adequate process margin. The polarization extinction ratios of 25 dB for the reflected light and 15 dB for the transmitted light were experimentally achieved at lambda=405 nm. The fabrication of the PBS is compatible with other micro diffractive elements to build a micro optical bench, thus, feasible for short wavelength optical storage applications. PMID:19503244

Lee, Chi-Hung; Chiu, Yi; Shieh, Han-Ping D

2005-12-12

345

When asking questions is not enough: an observational study of social communication differences in high functioning children with autism.  

PubMed

This investigation examined communication patterns between high functioning children with autism and their families and typically developing children and their families within traditional dinner time conversation. Twenty families with a child with autism (3.5-7 years.) and ten families with typically developing children (3.5-6 years) were video recorded during dinner and their interactions were coded. Results revealed that children with autism initiated fewer bids for interactions, commented less often, continued ongoing interactions through fewer conversational turns, and responded less often to family member communication bids. Results are interpreted with respect to how communication patterns may be indicative of social communication deficits not previously examined in high functioning children with autism. Strategies for social communication interventions within the family and other natural contexts are discussed. PMID:18784993

Jones, Christopher D; Schwartz, Ilene S

2008-09-11

346

Induction and decay of short-term heat acclimation in moderately and highly trained athletes.  

PubMed

A rethinking of current heat-acclimation strategies is required as most research and advice for improving physiological strain in the heat includes maintaining hydration using long-term acclimation protocols (>10 days). Furthermore, these strategies have tended to use untrained and moderately trained participants. Therefore, the aims of this review were to (i) investigate the effectiveness of short-term heat acclimation (STHA) with moderately and highly trained athletes; (ii) determine the importance of fluid regulatory strain, which has a thermally independent role in heat adaptation; (iii) assess the impact of STHA on a marker of thermotolerance (inducible heat-shock protein 70 [HSP70]); and (iv) provide further information on the decay of acclimation to heat. The review suggests that 5-day STHA is effective, and adaptations may be more pronounced after fluid regulatory strain from a dehydration-acclimation regimen. Furthermore, highly trained athletes may have similar physiological gains to those who are less trained using STHA. However, research has tended to focus on untrained or moderately trained participants and more information is required for highly trained populations. HSP70 response is upregulated across STHA. This indicates increased thermotolerance and protective adaptive change that may indicate HSP70 response as a useful marker of heat acclimation. Physiological adaptations after heat acclimation are relatively short term and may vanish only a few days or weeks after removal from heat exposure. From a practical perspective 5-day STHA may be the preferred acclimation regimen for moderately and highly trained athletes as it has been shown to be effective, less expensive and less likely to disrupt the tapering for competition in elite performers. Furthermore, updated information on the time course of acclimation decay may allow a reliable estimate of how long individuals can be free from heat exposure before reacclimation is required. This is particularly pertinent in present times as many athletes, civilians and military personnel increasingly have to relocate to different climates of the world, often within a short period of time. PMID:21846164

Garrett, Andrew T; Rehrer, Nancy J; Patterson, Mark J

2011-09-01

347

Milagro Constraints on Very High Energy Emission from Short-Duration Gamma-Ray Bursts  

NASA Astrophysics Data System (ADS)

Recent rapid localizations of short, hard gamma-ray bursts (GRBs) by the Swift and HETE satellites have led to the observation of the first afterglows and the measurement of the first redshifts from this type of burst (Fox et al. 2005; Gehrels et al. 2005; Villasenor et al. 2005; Berger et al. 2005; Barthelmy et al. 2005). Detection of >100 GeV counterparts would place powerful constraints on GRB mechanisms. Seventeen short-duration (<5 s) GRBs detected by satellites occurred within the field of view of the Milagro gamma-ray observatory between 2000 January and 2006 December. We have searched the Milagro data for >100 GeV counterparts to these GRBs and find no significant emission correlated with these bursts. Due to the absorption of high-energy gamma rays by the extragalactic background light (EBL), detections are only expected for redshifts less than ~0.5. While most long-duration GRBs occur at redshifts higher than 0.5, the opposite is thought to be true of short GRBs. Lack of a detected VHE signal thus allows setting meaningful fluence limits. One GRB in the sample (050509b) has a likely association with a galaxy at a redshift of 0.225, while another (051103) has been tentatively linked to the nearby galaxy M81. Fluence limits are corrected for EBL absorption, either using the known measured redshift, or computing the corresponding absorption for a redshift of 0.1 and 0.5, as well as for the case of z=0.

Abdo, A. A.; Allen, B. T.; Berley, D.; Blaufuss, E.; Casanova, S.; Dingus, B. L.; Ellsworth, R. W.; Gonzalez, M. M.; Goodman, J. A.; Hays, E.; Hoffman, C. M.; Kolterman, B. E.; Lansdell, C. P.; Linnemann, J. T.; McEnery, J. E.; Mincer, A. I.; Nemethy, P.; Noyes, D.; Ryan, J. M.; Samuelson, F. W.; Parkinson, P. M. Saz; Shoup, A.; Sinnis, G.; Smith, A. J.; Sullivan, G. W.; Vasileiou, V.; Walker, G. P.; Williams, D. A.; Xu, X. W.; Yodh, G. B.

2007-09-01

348

A highly reliable, autonomous data communication subsystem for an advanced information processing system  

NASA Astrophysics Data System (ADS)

The need to meet the stringent performance and reliability requirements of advanced avionics systems has frequently led to implementations which are tailored to a specific application and are therefore difficult to modify or extend. Furthermore, many integrated flight critical systems are input/output intensive. By using a design methodology which customizes the input/output mechanism for each new application, the cost of implementing new systems becomes prohibitively expensive. One solution to this dilemma is to design computer systems and input/output subsystems which are general purpose, but which can be easily configured to support the needs of a specific application. The Advanced Information Processing System (AIPS), currently under development has these characteristics. The design and implementation of the prototype I/O communication system for AIPS is described. AIPS addresses reliability issues related to data communications by the use of reconfigurable I/O networks. When a fault or damage event occurs, communication is restored to functioning parts of the network and the failed or damage components are isolated. Performance issues are addressed by using a parallelized computer architecture which decouples Input/Output (I/O) redundancy management and I/O processing from the computational stream of an application. The autonomous nature of the system derives from the highly automated and independent manner in which I/O transactions are conducted for the application as well as from the fact that the hardware redundancy management is entirely transparent to the application.

Nagle, Gail; Masotto, Thomas; Alger, Linda

1990-04-01

349

Thin-Film-Optics Design and Manufacturing Challenges for Large-Aperture High-Peak-Power, Short-Pulse Lasers  

SciTech Connect

High-peak-power, short-pulse laser systems require specialized thin-film coatings, primarily due to laser damage thresholds and increased spectral bandwidth. The influence of these effects is evident in wavefront performance, coating thickness, and design complexity.

Oliver,J.B.

2004-12-17

350

Characteristics of high energy K? and Bremsstrahlung sources generated by short pulse petawatt lasers  

NASA Astrophysics Data System (ADS)

We have measured the characteristics of high energy K? sources created with the Vulcan Petawatt laser at RAL and the JanUSP laser at Lawrence Livermore National Laboratory. High energy x-ray backlighters will be essential for radiographing high energy-density experimental science targets for NIF projects especially to probe implosions and high areal density planar samples. Hard K? x-ray photons are created through relativistic electron plasma interactions in the target material after irradiated by short pulse high intensity lasers. For our Vulcan experiment, we employed a CsI scintillator charge coupled device (CCD) camera for imaging and a CCD camera for single photon counting. We have directly measured the 22 keV Ag K? source size using the RAL petawatt laser and performed knife-edge measurements of a 40 keV Sm K? source using the JanUSP laser. The measured source sizes are both ~60 ?m full width half maximum. We have also measured the Ag K? conversion efficiencies. At laser intensities of 1×1018 W/cm2 range, the conversion efficiency at 22 keV is ~1×10-4.

Park, H.-S.; Izumi, N.; Key, M. H.; Koch, J. A.; Landen, O. L.; Patel, P. K.; Phillips, T. W.; Zhang, B. B.

2004-10-01

351

Highly-charged heavy-ion production with short pulse lasers  

SciTech Connect

This MathCAD document describes a possible approach using a PW -class short pulse laser to form a useful number (10{sup 12}) of high and uniform charge state ions with low ion temperature (<< 100 eV) and low momentum spread ({delta}p{sub z}/p, < 10{sup -4} ) for injection into heavy-ion fusion accelerators. As a specific example, we consider here Xenon{sup +26}, which has an ionization energy E{sub i} {approximately} 860 eV for the 26th electron, and a significantly higher ionization potential of 1500 eV for the 27th electron because of the M-shell jump. The approach considered here may be used for other ion species as well. The challenge is not simply to produce high charge states with a laser (the ITEP group [Sharkov] have used long pulse CO{sub 2} lasers to create many charge states of chromium up to helium-like Cr{sup +25} by collisional ionization at high Te), nor just to create such high charge states more selectively by field (tunneling) ionization at higher intensities and shorter pulses. Rather, the challenge is to create a selected uniform high charge state, in useful numbers, while keeping the ion temperature and momentum spread small, and avoiding subsequent loss of ion charge state due to recombination and charge-exchange with background gas atoms during extraction into a useful low emittance beam.

Logan, G.; Bitmire, T.; Perry, M.; Anderson, O.; Kuehl, T.

1998-01-27

352

Advances in high-throughput speed, low-latency communication for embedded instrumentation ( 7th Annual SFAF Meeting, 2012)  

ScienceCinema

Scott Jordan on "Advances in high-throughput speed, low-latency communication for embedded instrumentation" at the 2012 Sequencing, Finishing, Analysis in the Future Meeting held June 5-7, 2012 in Santa Fe, New Mexico.

353

Effects of short-term, high dose, heparin therapy on biochemical markers of bone metabolism.  

PubMed

To evaluate the effects of the short-term, high-dose sodium heparin therapy on biochemical markers of bone metabolism, we studied 20 patients (11 males and 9 females) with pulmonary embolism, treated with sodium heparin (daily dose range: 40,000-45,000 I.U. by continuous i.v. infusion). Heparin therapy lasted 5-7 days, after which patients received warfarin over 12 months. Eleven patients (6 males and 5 females) with ischaemic stroke, treated with i.v. glycerol and pentoxifilline, were used as controls. Before and after therapy serum and urinary markers of bone metabolism were evaluated; in 12 heparin-treated pts., the parameters were also evaluated 4 months after discontinuation of warfarin therapy. After heparin therapy a significant reduction vs. basal value was observed in levels of serum osteocalcin (ng/ml;mean + SEM): 3.32 & 0.19 vs. 2.05 + 0.21; p < 0.001. In the 12 patients evaluated 4 months after discontinuation of warfarin therapy, serum osteocalcin levels returned to basal value: 3.41 + 0.12 ng/ml (p:n.s.). No significant changes of the examined parameters were observed in controls. In conclusion, our data seem to indicate an effect of i.v. short-term heparin therapy on bone metabolism. This effect seems to be characterized by an inhibition of osteoblast function as suggested by the reduction of serum osteocalcin levels. PMID:8608685

Cantini, F; Niccoli, L; Bellandi, F; Di Munno, O

1995-11-01

354

Quercetin alleviates inflammation after short-term treatment in high-fat-fed mice.  

PubMed

Consumption of a high-fat diet (HFD) promotes reactive oxygen species (ROS) which ultimately trigger inflammation. The aim of this study was to investigate the role of Moringa oleifera leaf extract (MoLE) and its active component quercetin in preventing NF-?B-mediated inflammation raised by short-term HFD. Quercetin was found to be one of the major flavonoid components from HPLC of MoLE. Swiss mice were fed for 15 days on HFD, both with or without MoLE/quercetin. The antioxidant profile was estimated from liver homogenate. NF-?B and some relevant inflammatory markers were evaluated by immunoblotting, RT-PCR and ELISA. Significantly (P < 0.05) lower antioxidant profile and higher lipid peroxidation was found in HFD group compared to control (P < 0.05). Increased nuclear import of NF-?B and elevated expressions of pro-inflammatory markers were further manifestations in the HFD group. All these changes were reversed in the MoLE/quercetin-treated groups with significant improvement of antioxidant activity compared to the HFD group. MoLE was found to be rich in polyphenols and both MoLE and quercetin showed potent free radical and hydroxyl radical quenching activity. Thus, the present study concluded that short-term treatment with MoLE and its constituent quercetin prevent HFD-mediated inflammation in mice. PMID:23644882

Das, Nilanjan; Sikder, Kunal; Bhattacharjee, Surajit; Majumdar, Suchandra Bhattacharya; Ghosh, Santinath; Majumdar, Subrata; Dey, Sanjit

2013-05-03

355

AquaOptical: A lightweight device for high-rate long-range underwater point-to-point communication  

Microsoft Academic Search

This paper describes AquaOptical, an underwater optical communication system. Three optical modems have been developed: a long range system, a short range system, and a hybrid. We describe their hardware and software architectures and highlight trade-offs. We present pool and ocean experiments with each system. In clear water AquaOptical was tested to achieve a data rate of 1.2 Mbit\\/sec at

Marek Doniec; Iuliu Vasilescu; Mandar Chitre; Carrick Detweiler; Matthias Hoffmann-Kuhnt; Daniela Rus

2009-01-01

356

Core Communications  

ERIC Educational Resources Information Center

|The website--it is where people go to find out anything and everything about a school, college, or university. In the relatively short life of the Internet, institutional websites have moved from the periphery to center stage and become strategically integral communications and marketing tools. As the flow of information accelerates and new…

Block, Greg; Ross, J. D.; Mulder, David

2011-01-01

357

Feasible Study of Road-to-Vehicle Communication System using LED Array and High-Speed Camera  

Microsoft Academic Search

In this study, we focus attention on the parallel optical wireless communication systems using LED array transmitter and a high-speed camera as the receiver for road-to-vehicle communications in ITS. Previously, we have proposed a hierarchical coding scheme which allocates data to spatial frequency components depending on the priority. This scheme is possible to receive the high priority data even if

Shintaro ARAI; Shohei MASE; Takaya YAMAZATO; Tomohiro YENDO; Toshiaki FUJII; Masayuki TANIMOTO; Yoshikatsu KIMURA

358

High-speed-camera image processing based LED traffic light detection for road-to-vehicle visible light communication  

Microsoft Academic Search

As one of ITS technique, a new visible light road-to-vehicle communication system at intersections is proposed. In this system, the communication between a vehicle and an LED traffic light is conducted using an LED traffic light as a transmitter, and an on-vehicle high-speed camera as a receiver. The LEDs in the transmitter emit light in high frequency and those emitting

H. C. N. Premachandra; T. Yendo; M. P. Tehrani; T. Yamazato; H. Okada; T. Fujii; M. Tanimoto

2010-01-01

359

An integrated optical/acoustic communication system for seafloor observatories: A field test of high data rate communications at CORK 857D  

NASA Astrophysics Data System (ADS)

We report the successful deployment and testing of an underwater optical communication system that provides high data rate communications over a range of 100 meters from a deep sea borehole observatory located in the northeast Pacific. Optical underwater communications offers many advantages over acoustic or underwater wet mateable connections (UWMC). UMWCs requires periodic visits from a submersible or ROV to plug in and download data. Typically, these vehicles cannot perform any other tasks during these download periods - their time on station is limited, restricting the amount of data that can be downloaded. To eliminate the need for UWMCs requires the use of remote communication techniques such as acoustics or optical communications. Optical communications is capable of high data rates up to 10 mega bits per sec (Mbps) compared to acoustic data rates of 57 Kbps. We have developed an integrated optical/acoustic telemetry system (OTS) that uses an acoustic command system to control a high bandwidth, low latency optical communication system. In July 2010, we used the deep submersible ALVIN to install the Optical Telemetry System (OTS) at CORK 857D. The CORK is instrumented with a thermistor string and pressure sensors that record downhole formation pressures and temperatures within oceanic basement that is pressure sealed from the overlying water column. The seafloor OTS was plugged into the CORK’s existing UWMC to provide an optical and acoustic communication interface and additional data storage and battery power for the CORK to sample at 1 Hz data-rate, an increase over the normal 15 sec data sample rate. Using a CTD-mounted OTS lowered by wire from a surface ship, we established an optical communication link at 100 meters range at rates of 1, 5 and 10 Mbps with no bit errors. Tests were also done to establish the optical range of various data rates and the optical power of the system. After a week, we repeated the CTD-OTS experiment and downloaded 20 Mbytes of data over a 5 Mbps link at a range of 80 m. The OTS will remain installed at CORK 857D for a year. Our OTS enables faster data rates to be employed for in situ measurements that were previously limited by data download times from a submersible. The OTS also permits non submersible-equipped vessels to interrogate the CORK borehole observatory on a more frequent basis using a receiver lowered by wire from a ship of opportunity. In the future, autonomous vehicles could interrogate such seafloor observatories in a “data-mule” configuration and then dock at a seafloor cabled node to download data. While borehole observatories may ultimately be linked into undersea cables relaying real-time data back to shore they represent a superb opportunity to test free water optical communication methods. The lessons learned from our CORK development efforts will go a long way towards establishing the viability of underwater optical communications for a host of autonomous seafloor sensor systems in the future.

Tivey, M.; Farr, N.; Ware, J.; Pontbriand, C.

2010-12-01

360

High linearity current communicating passive mixer employing a simple resistor bias  

NASA Astrophysics Data System (ADS)

A high linearity current communicating passive mixer including the mixing cell and transimpedance amplifier (TIA) is introduced. It employs the resistor in the TIA to reduce the source voltage and the gate voltage of the mixing cell. The optimum linearity and the maximum symmetric switching operation are obtained at the same time. The mixer is implemented in a 0.25 ?m CMOS process. The test shows that it achieves an input third-order intercept point of 13.32 dBm, conversion gain of 5.52 dB, and a single sideband noise figure of 20 dB.

Rongjiang, Liu; Guiliang, Guo; Yuepeng, Yan

2013-03-01

361

A Pragmatic Coded Modulation Scheme for High-Spectral-Efficiency Fiber-Optic Communications  

NASA Astrophysics Data System (ADS)

A pragmatic coded modulation system is presented that incorporates signal shaping and exploits the excellent performance and efficient high-speed decoding architecture of staircase codes. Reliable communication within 0.62 bits/s/Hz of the estimated capacity (per polarization) of a system with L=2000 km is provided by the proposed system, with an error floor below 1E-20. Also, it is shown that digital backpropagation increases the achievable spectral efficiencies---relative to linear equalization---by 0.55 to 0.75 bits/s/Hz per polarization.

Smith, Benjamin P.; Kschischang, Frank R.

2012-07-01

362

Differential sensitivity of long-sleep and short-sleep mice to high doses of cocaine.  

PubMed

The cocaine sensitivity of male and female long-sleep (LS) and short-sleep (SS) mice, which have been selectively bred for differential ethanol-induced "sleep-time," was examined in a battery of behavioral and physiological tests. Differences between these two mouse lines were subtle and were seen primarily at high doses. At high doses, SS mice were more sensitive than LS mice, particularly to cocaine-induced hypothermia; however, significant hypothermia was not seen except at doses which were very near to the seizure threshold. During a 60-min test of locomotor activity, LS mice showed greater stimulation of Y-maze activity by 20 mg/kg cocaine than SS mice. Consistent with the finding of subtle differences in sensitivity to low doses of cocaine. LS and SS mice did not differ in sensitivity to cocaine inhibition of synaptosomal uptake of [3H]-dopamine, [3H]-norepinephrine or [3H]-5-hydroxytryptamine. However, consistent with the finding of differential sensitivity to high doses of cocaine, SS mice were more sensitive to the seizure-producing effects of the cocaine and lidocaine, a local anesthetic. It is hypothesized that the differential sensitivity of these mouse lines to high doses of cocaine is due to differential sensitivity to cocaine's actions on systems that regulate local anesthetic effects. Selective breeding for differential duration of alcohol-induced "sleep-time" may have resulted in differential ion channel structure or function in these mice. PMID:2623042

de Fiebre, C M; Ruth, J A; Collins, A C

1989-12-01

363

Crosstalk canceling pattern for high-speed communications and modular jack having the same  

US Patent & Trademark Office Database

Disclosed herein are a crosstalk canceling pattern for high-speed communications and a modular jack having the same, which includes a compensating capacitor on a transmission line to cancel crosstalk due to parasitic capacitance generated between neighboring insert pins, and includes a second compensating capacitor to correct phase mismatch due to parasitic inductance generated in insert pins and transmission lines, when a high-frequency signal is applied. The modular jack having the crosstalk canceling pattern for high-speed communications includes a housing, a printed circuit board, a lower contact block, and an upper contact block. The hosing includes a plug insert hole, an insert pin locking plate, and a coupling guide part. The printed circuit board is a multi-layered structure having a plurality of compensating capacitors. The lower contact block is mounted to the lower surface of the printed circuit board. The upper contact block is mounted to the upper portion of the lower contact block, and divides UTP cable wires to be connected to IDC terminals.

Kim; Dae Sung (Gunpo-si, KR); Kim; Jung Gon (Siheung-si, KR); Lee; Jung Suk (Seoul-si, KR); Kim; Su Jong (Anyang-si, KR)

2007-02-13

364

Short pulse, high power microwave radiation source with a laser-induced sheet plasma mirror  

SciTech Connect

We have demonstrated the short pulse, high power microwave radiation source using an ultraviolet laser-induced sheet plasma mirror in a gas-filled x-band rectangular waveguide from the conventional microwave sources and components. A laser-induced sheet plasma with an overdense plasma acts as a plasma mirror. The long pulse propagating in the gas-filled waveguide was sliced by the sheet plasma mirror at two different points along the waveguide. We observed about twice the power of the pulse by adding the two sliced microwave pulses produced by this scheme. A maximum peak power of 200 kW with a pulse duration of 10 ns (full width at half maximum) from the long microwave pulse source with a pulse duration of 0.8 mus was observed.

Higashiguchi, Takeshi; Yugami, Noboru [Graduate School of Engineering and Center for Optical Research and Education (CORE), Utsunomiya University, Yoto 7-1-2, Utsunomiya, Tochigi 321-8585 (Japan)

2009-05-01

365

Point-spread function reconstruction in high aperture lenses focusing ultra-short laser pulses  

NASA Astrophysics Data System (ADS)

In this paper we discuss the measurement of the amplitude point-spread function (PSF) of high aperture lenses focusing ultrashort laser pulses. In the experimental set-up a Twyman-Green interferometer and an autocorrelator are combined to function as a phase-shifting interferometer which is then used to measure the phase distribution in the pupil plane of the lens. Numerical reconstruction of the interferograms permits us to calculate the spatial distribution of the amplitude and phase of the point-spread function. Our work is relevant for cases when ultra-short laser pulses are focused for applications such as two- and three-photon fluorescence, second- and third-harmonic generation microscopy, optical coherence tomography and microscopy, and optical data storage.

Török, Peter; Kao, Fu-Jen

2002-11-01

366

Towards shorter wavelength x-ray lasers using a high power, short pulse pump laser  

SciTech Connect

A near-terawatt, KrF* laser system, focussable to power densities >10{sup 18} W/cm{sup 2} has been constructed for use as a pump laser in various schemes aimed at the development of x-ray lasing below 5nm. The laser system along with output characteristics such as the pulse duration, the focal spot size, and the percentage of amplified spontaneous emission (ASE) emitted along with the laser pulse will be presented. Schemes intended to lead to shorter wavelength x-ray emission will be described. The resultant requirements on the pump laser characteristics and the target design will be outlined. Results from recent solid target experiments and two-laser experiments, showing the interaction of a high-power, short pulse laser with a preformed plasma, will be presented. 13 refs., 5 figs.

Tighe, W.; Krushelnick, K.; Valeo, E.; Suckewer, S.

1991-05-01

367

Epithermal Neutron Source for Neutron Resonance Spectroscopy (NRS) using High Intensity, Short Pulse Lasers  

SciTech Connect

A neutron source for neutron resonance spectroscopy (NRS) has been developed using high intensity, short pulse lasers. This measurement technique will allow for robust measurements of interior ion temperature of laser-shocked materials and provide insight into equation of state (EOS) measurements. The neutron generation technique uses protons accelerated by lasers off of Cu foils to create neutrons in LiF, through (p,n) reactions with {sup 7}Li and {sup 19}F. The distribution of the incident proton beam has been diagnosed using radiochromic film (RCF). This distribution is used as the input for a (p,n) neturon prediction code which is compared to experimentally measured neutron yields. From this calculation, a total fluence of 1.8 x 10{sup 9} neutrons is infered, which is shown to be a reasonable amount for NRS temperature measurement.

Higginson, D P; McNaney, J M; Swift, D C; Bartal, T; Hey, D S; Pape, S L; Mackinnon, A; Mariscal, D; Nakamura, H; Nakanii, N; Beg, F N

2010-04-22

368

High Short-Term Loosening Rates with the Wagner Standard Cup.  

PubMed

The stability of prosthetic fixation is to a large extent dependent on component design. The purpose of this study is to analyze the short-term radiological results obtained with the Wagner Standard Cup in primary hip arthroplasty. An assessment was made of one hundred primary hip arthroplasties. The radiological evaluation revealed bone ingrowth in 37 of cases, fibrous integration in 49 and loosening in 14. In summary, osseointegration of the Wagner Standard Cup was unsuccessful in a high percentage of cases. This finding, which was unrelated to the type of stem or bearing surface used, bore a statistically significant relation (P<0.05) with an observed poor bone coverage of the acetabular component. Although insufficient bone coverage could arguably be attributable to a poor surgical technique, we would tend to agree with other authors that it is rather likely to result from a flawed implant design that impedes osseointegration. PMID:23643713

Ros, Vanesa; Martínez Alvarez, Marta; Fernández, Salvador; Girvent, Ramon; Carballo, Alejandro; Gili, Gabriel; Torner, Pere

2013-05-01

369

Integrated multichannel photon timing instrument with very short dead time and high throughput  

NASA Astrophysics Data System (ADS)

Precisely timed detection of single photons plays an important role in the field of quantum information processing and fluorescence sensing. The method of time-correlated single photon counting is therefore constantly evolving and the associated instrumentation is being improved with new ideas and technologies. Simultaneous, time tagged readout of multiple detector channels is invaluable in many applications, spanning from fluorescence lifetime imaging in biology to the measurement of quantum optical correlations in basic research. Here we present a new integrated design, providing up to three independent input channels, a very short dead time, very high throughput, and a timing resolution of 25 ps at reasonable cost and small size. Apart from design features and test results of the instrument, we show an application in quantum optics, namely, the measurement of the photon statistics of a heralded single photon source based on cavity-enhanced spontaneous parametric down-conversion.

Wahl, Michael; Röhlicke, Tino; Rahn, Hans-Jürgen; Erdmann, Rainer; Kell, Gerald; Ahlrichs, Andreas; Kernbach, Martin; Schell, Andreas W.; Benson, Oliver

2013-04-01

370

Integrated multichannel photon timing instrument with very short dead time and high throughput.  

PubMed

Precisely timed detection of single photons plays an important role in the field of quantum information processing and fluorescence sensing. The method of time-correlated single photon counting is therefore constantly evolving and the associated instrumentation is being improved with new ideas and technologies. Simultaneous, time tagged readout of multiple detector channels is invaluable in many applications, spanning from fluorescence lifetime imaging in biology to the measurement of quantum optical correlations in basic research. Here we present a new integrated design, providing up to three independent input channels, a very short dead time, very high throughput, and a timing resolution of 25 ps at reasonable cost and small size. Apart from design features and test results of the instrument, we show an application in quantum optics, namely, the measurement of the photon statistics of a heralded single photon source based on cavity-enhanced spontaneous parametric down-conversion. PMID:23635176

Wahl, Michael; Röhlicke, Tino; Rahn, Hans-Jürgen; Erdmann, Rainer; Kell, Gerald; Ahlrichs, Andreas; Kernbach, Martin; Schell, Andreas W; Benson, Oliver

2013-04-01

371

High power, short pulses ultraviolet laser for the development of a new x-ray laser  

SciTech Connect

A high power, short pulse ultraviolet laser system (Powerful Picosecond-Laser) has been developed at the Princeton Plasma Physics Laboratory (PPPL) as part of experiments designed to generate shorter wavelength x-ray lasers. With the addition of pulse compression and a final KrF amplifier the laser output is expected to have reached 1/3-1/2 TW (10/sup 12/ watts) levels. The laser system, particularly the final amplifier, is described along with some initial soft x-ray spectra from laser-target experiments. The front end of the PP-Laser provides an output of 20--30 GW (10/sup 9/ watts) and can be focussed to intensities of /approximately/10/sup 16/ W/cm/sup 2/. Experiments using this output to examine the effects of a prepulse on laser-target interaction are described. 19 refs., 14 figs.

Meixler, L.; Nam, C.H.; Robinson, J.; Tighe, W.; Krushelnick, K.; Suckewer, S.; Goldhar, J.; Seely, J.; Feldman, U.

1989-04-01

372

Experimental Evaluation of Body Channel Response and Digital Modulation Schemes for Intra-body Communications  

Microsoft Academic Search

Intra-body communications is a short range communication solution suitable for Body Area Networks wherein the human body is used as the transmission medium. Currently, some studies have succeeded to transmit and receive simple information. However, intra-body communications could also provide broadband applications such as video streaming which will need high data rates. In this paper, firstly we investigate the propagation

Jordi Agud Ruiz; Shigeru Shimamoto

2006-01-01

373

Effectiveness of short-term heat acclimation for highly trained athletes.  

PubMed

Effectiveness of short-term acclimation has generally been undertaken using untrained and moderately-trained participants. The purpose of this study was to determine the impact of short-term (5-day) heat acclimation on highly trained athletes. Eight males (mean ± SD age 21.8 ± 2.1 years, mass 75.2 ± 4.6 kg, VO(2peak) 4.9 ± 0.2 L min(-1) and power output 400 ± 27 W) were heat acclimated under controlled hyperthermia (rectal temperature 38.5 °C), for 90-min on five consecutive days (T(a) = 39.5 °C, 60% relative humidity). Acclimation was undertaken with dehydration (no fluid-intake) during daily bouts. Participants completed a rowing-specific, heat stress test (HST) 1 day before and after acclimation (T(a) = 35 °C, 60% relative humidity). HST consisted 10-min rowing at 30% peak power output (PPO), 10 min at 60% PPO and 5-min rest before a 2-km performance test, without feedback cues. Participants received 250 mL fluid (4% carbohydrate; osmolality 240-270 mmol kg(-1)) before the HST. Body mass loss during acclimation bouts was 1.6 ± 0.3 kg (2.1%) on day 1 and 2.3 ± 0.4 kg (3.0%) on day 5. In contrast, resting plasma volume increased by 4.5 ± 4.5% from day 1 to 5 (estimated from [Hb] & Hct). Plasma aldosterone increased at rest (52.6 pg mL(-1); p = 0.03) and end-exercise (162.4 pg mL(-1); p = 0.00) from day 1 to 5 acclimation. During the HST T(re) and f(c) were lowered 0.3 °C (p = 0.00) and 14 b min(-1) (p = 0.00) after 20-min exercise. The 2-km performance time (6.52.7 min) improved by 4 s (p = 0.00). Meaningful physiological and performance improvements occurred for highly trained athletes using a short-term (5-day) heat acclimation under hyperthermia control, with dehydration. PMID:21915701

Garrett, Andrew T; Creasy, Rob; Rehrer, Nancy J; Patterson, Mark J; Cotter, James D

2011-09-14

374

High efficiency video coding for ultrasound video communication in m-health systems.  

PubMed

Emerging high efficiency video compression methods and wider availability of wireless network infrastructure will significantly advance existing m-health applications. For medical video communications, the emerging video compression and network standards support low-delay and high-resolution video transmission, at the clinically acquired resolution and frame rates. Such advances are expected to further promote the adoption of m-health systems for remote diagnosis and emergency incidents in daily clinical practice. This paper compares the performance of the emerging high efficiency video coding (HEVC) standard to the current state-of-the-art H.264/AVC standard. The experimental evaluation, based on five atherosclerotic plaque ultrasound videos encoded at QCIF, CIF, and 4CIF resolutions demonstrates that 50% reductions in bitrate requirements is possible for equivalent clinical quality. PMID:23366352

Panayides, A; Antoniou, Z; Pattichis, M S; Pattichis, C S; Constantinides, A G

2012-01-01

375

Enduring Medial Perforant Path Short-Term Synaptic Depression at High Pressure  

PubMed Central

The high pressure neurological syndrome develops during deep-diving (>1.1 MPa) involving impairment of cognitive functions, alteration of synaptic transmission and increased excitability in cortico-hippocampal areas. The medial perforant path (MPP), connecting entorhinal cortex with the hippocampal formation, displays synaptic frequency-dependent-depression (FDD) under normal conditions. Synaptic FDD is essential for specific functions of various neuronal networks. We used rat cortico-hippocampal slices and computer simulations for studying the effects of pressure and its interaction with extracellular Ca2+ ([Ca2+]o) on FDD at the MPP synapses. At atmospheric pressure, high [Ca2+]o (4–6?mM) saturated single MPP field EPSP (fEPSP) and increased FDD in response to short trains at 50?Hz. High pressure (HP; 10.1 MPa) depressed single fEPSPs by 50%. Increasing [Ca2+]o to 4?mM at HP saturated synaptic response at a subnormal level (only 20% recovery of single fEPSPs), but generated a FDD similar to atmospheric pressure. Mathematical model analysis of the fractions of synaptic resources used by each fEPSP during trains (normalized to their maximum) and the total fraction utilized within a train indicate that HP depresses synaptic activity also by reducing synaptic resources. This data suggest that MPP synapses may be modulated, in addition to depression of single events, by reduction of synaptic resources and then may have the ability to conserve their dynamic properties under different conditions.

Talpalar, Adolfo E.; Giugliano, Michele; Grossman, Yoram

2010-01-01

376

GaAs Photonic Integrated Circuit (PIC) development for high performance communications  

SciTech Connect

Sandia has established a foundational technology in photonic integrated circuits (PICs) based on the (Al,Ga,In)As material system for optical communication, radar control and testing, and network switching applications at the important 1.3{mu}m/1.55{mu}m wavelengths. We investigated the optical, electrooptical, and microwave performance characteristics of the fundamental building-block PIC elements designed to be as simple and process-tolerant as possible, with particular emphasis placed on reducing optical insertion loss. Relatively conventional device array and circuit designs were built using these PIC elements: (1) to establish a baseline performance standard; (2) to assess the impact of epitaxial growth accuracy and uniformity, and of fabrication uniformity and yield; (3) to validate our theoretical and numerical models; and (4) to resolve the optical and microwave packaging issues associated with building fully packaged prototypes. Novel and more complex PIC designs and fabrication processes, viewed as higher payoff but higher risk, were explored in a parallel effort with the intention of meshing those advances into our baseline higher-yield capability as they mature. The application focus targeted the design and fabrication of packaged solitary modulators meeting the requirements of future wideband and high-speed analog and digital data links. Successfully prototyped devices are expected to feed into more complex PICs solving specific problems in high-performance communications, such as optical beamforming networks for phased array antennas.

Sullivan, C.T.

1998-03-01

377

The influence of high\\/low-context culture and power distance on choice of communication media: Students’ media choice to communicate with Professors in Japan and America  

Microsoft Academic Search

This study focuses on two widely used cultural constructs, high-context (HC)\\/low-context (LC) culture, and power distance (PD), and investigates their influence on media choice behavior. The propositions that Japan is a higher context and PD culture than the United States were tested. The study also explored the association between individual cultural values and choice of communication media. The results, the

Rieko Maruta Richardson; Sandi W. Smith

2007-01-01

378

Ain't no mountain high enough? Setting high weight loss goals predict effort and short-term weight loss.  

PubMed

Although psychological theories outline that it might be beneficial to set more challenging goals, people attempting to lose weight are generally recommended to set modest weight loss goals. The present study explores whether the amount of weight loss individuals strive for is associated with more positive psychological and behavioral outcomes. Hereto, 447 overweight and obese participants trying to lose weight completed two questionnaires with a 2-month interval. Many participants set goals that could be considered unrealistically high. However, higher weight loss goals did not predict dissatisfaction but predicted more effort in the weight loss attempt, as well as more self-reported short-term weight loss when baseline commitment and motivation were controlled for. PMID:22933574

De Vet, Emely; Nelissen, Rob M A; Zeelenberg, Marcel; De Ridder, Denise T D

2012-08-29

379

Plasma PCSK9 concentrations during an oral fat load and after short term high-fat, high-fat high-protein and high-fructose diets  

PubMed Central

Background PCSK9 (Proprotein Convertase Subtilisin Kexin type 9) is a circulating protein that promotes hypercholesterolemia by decreasing hepatic LDL receptor protein. Under non interventional conditions, its expression is driven by sterol response element binding protein 2 (SREBP2) and follows a diurnal rhythm synchronous with cholesterol synthesis. Plasma PCSK9 is associated to LDL-C and to a lesser extent plasma triglycerides and insulin resistance. We aimed to verify the effect on plasma PCSK9 concentrations of dietary interventions that affect these parameters. Methods We performed nutritional interventions in young healthy male volunteers and offspring of type 2 diabetic (OffT2D) patients that are more prone to develop insulin resistance, including: i) acute post-prandial hyperlipidemic challenge (n=10), ii) 4 days of high-fat (HF) or high-fat/high-protein (HFHP) (n=10), iii) 7 (HFruc1, n=16) or 6 (HFruc2, n=9) days of hypercaloric high-fructose diets. An acute oral fat load was also performed in two patients bearing the R104C-V114A loss-of-function (LOF) PCSK9 mutation. Plasma PCSK9 concentrations were measured by ELISA. For the HFruc1 study, intrahepatocellular (IHCL) and intramyocellular lipids were measured by 1H magnetic resonance spectroscopy. Hepatic and whole-body insulin sensitivity was assessed with a two-step hyperinsulinemic-euglycemic clamp (0.3 and 1.0 mU.kg-1.min-1). Findings HF and HFHP short-term diets, as well as an acute hyperlipidemic oral load, did not significantly change PCSK9 concentrations. In addition, post-prandial plasma triglyceride excursion was not altered in two carriers of PCSK9 LOF mutation compared with non carriers. In contrast, hypercaloric 7-day HFruc1 diet increased plasma PCSK9 concentrations by 28% (p=0.05) in healthy volunteers and by 34% (p=0.001) in OffT2D patients. In another independent study, 6-day HFruc2 diet increased plasma PCSK9 levels by 93% (p<0.0001) in young healthy male volunteers. Spearman’s correlations revealed that plasma PCSK9 concentrations upon 7-day HFruc1 diet were positively associated with plasma triglycerides (r=0.54, p=0.01) and IHCL (r=0.56, p=0.001), and inversely correlated with hepatic (r=0.54, p=0.014) and whole-body (r=?0.59, p=0.0065) insulin sensitivity. Conclusions Plasma PCSK9 concentrations vary minimally in response to a short term high-fat diet and they are not accompanied with changes in cholesterolemia upon high-fructose diet. Short-term high-fructose intake increased plasma PCSK9 levels, independent on cholesterol synthesis, suggesting a regulation independent of SREBP-2. Upon this diet, PCSK9 is associated with insulin resistance, hepatic steatosis and plasma triglycerides.

2013-01-01

380

Communication acoustics  

NASA Astrophysics Data System (ADS)

Those aspects of acoustics which concern the relations of acoustics to the information and communication technologies are now frequently called ``communication acoustics.'' After a short review of the history of this field, relevant results from recent research at the Institute of Communication Acoustics at the Ruhr-University of Bochum, Germany, will be reported. This work can be seen in light of the research areas of computational auditory scene analysjs (CASA) and auditory virtual environments (AVE)-both dealing with the parametric representation of auditory scenes. Recent application opportunities and future trends will be discussed. It will be argued that modern communication-acoustical systems-which are often only embedded components in more complex communication systems-require more and more built-in explicit knowledge. Among other things, the development of such components and systems calls for data and knowledge from the cognitive sciences. Today's programs for education in communication engineering and communication acoustics often do not take sufficient account of this trend.

Blauert, Jens

2001-05-01

381

Evolution of a new drug formulation: the rationale for high-dose, short-course therapy with azithromycin  

Microsoft Academic Search

The rationale for the use of high-dose, short-course azithromycin treatment regimens is based on the pharmacokinetic properties of azithromycin. Its long elimination half-life (?60 h) and antibacterial potency make short-course (1-day) regimens feasible. Azithromycin is concentrated within phagocytic cells, which deliver it in a targeted manner to sites of infection. In vitro and in vivo models demonstrate that azithromycin is

Jeffrey L. Blumer

2005-01-01

382

Grand Challenges: High Performance Computing and Communications. The FY 1992 U.S. Research and Development Program.  

ERIC Educational Resources Information Center

|This report presents a review of the High Performance Computing and Communications (HPCC) Program, which has as its goal the acceleration of the commercial availability and utilization of the next generation of high performance computers and networks in order to: (1) extend U.S. technological leadership in high performance computing and computer…

Federal Coordinating Council for Science, Engineering and Technology, Washington, DC.

383

Improved High-Force Magnetic Tweezers for Stretching and Refolding of Proteins and Short DNA  

PubMed Central

Although magnetic tweezers have many unique advantages in terms of specificity, throughput, and force stability, this tool has had limited application on short tethers because accurate measurement of force has been difficult for short tethers under large tension. Here, we report a method that allows us to apply magnetic tweezers to stretch short biomolecules with accurate force calibration over a wide range of up to 100 pN. We demonstrate the use of the method by overstretching of a short DNA and unfolding/refolding a protein of filamin A immunoglobulin domains 1–8. Other potential applications of this method are also discussed.

Chen, Hu; Fu, Hongxia; Zhu, Xiaoying; Cong, Peiwen; Nakamura, Fumihiko; Yan, Jie

2011-01-01

384

Optimal design of high frequency readout IC for short-wave IRFPA  

NASA Astrophysics Data System (ADS)

High frequency readout-integrated circuit(ROIC) of 512×256 staring short wavelength(SW) infrared focal plane arrays(IRFPAs), focusing on high-frame rate output and noise suppression is implemented in this paper. The design of ROIC mentioned in it takes the previous version into account. The complete analog signal chain contains a novel input stage of capacitor feedback transimpedance amplifier(CTIA) preamplifier, a CDS (correlated double sampling) module, an amplifier of charge and complementary output stage. This ROIC is a full-custom flow integrated circuit design. The parasitic parameters are extracted once the layout is finished. Then the design is improved according to the result of post-layout simulation, which leads to the great improvements of the majority of parameters. The test and simulation results show that the output voltage range is 2.8V, the frame rate is 250Hz and the linearity within useful voltage range is above 99.1 percent, even when the temperature is 77K.

Wang, Pan; Chen, Guo-qiang; Gao, Lei; Zhou, Jie; Ding, Rui-jun

2012-12-01

385

Beam dynamics in a high brightness linac for short wavelength SASE-FEL experiments  

NASA Astrophysics Data System (ADS)

Short wavelength SASE-FEL requires generation and transport up to the undulator entrance of low emittance (~1 2 mm mrad) high peak current (~1 3 kA) electron beams with energy higher than 1 GeV. The propagation of such a high brightness beam takes place in a transition regime from space charge to emittance dominated dynamics, as the beam energy increases. In addition, in downstream magnetic compressor devices where the peak current increases up to kA range, the transition may occur again. Under these conditions, the electron beam has to be properly matched to the linac accelerating sections in order to keep under control emittance oscillations driven by residual space charge effects. Generalized invariant envelope matching conditions are discussed in this paper, showing that an equilibrium between RF focusing forces and space charge/emittance defocusing forces can be attained without any additional external focusing along the linac (no quadrupoles), thus reducing alignment problems and mitigating emittance dilutions due to misalignments and beam parameter jitters.

Ferrario, M.; Fusco, V.; Ronsivalle, C.; Serafini, L.; Vaccarezza, C.

2006-11-01

386

Short-Pulse High-Intensity Laser Generated Electrons Transport in solid targets  

NASA Astrophysics Data System (ADS)

Understanding the propagation and energy deposition of relativistic electrons generated by high-Intensity short-pulse laser is essential to fast ignition. We conducted a systematic study of the electron beam energy transport using the Vulcan laser facility in the United Kingdom. The laser Energy was 400 J delivered in either 1ps or 10ps. We used a 5 ?m thick Molybdenum targets with two different layers. The Vanadium layer was 1 ?m thick and located at the back of the target. The Nickel layer was 0.5 ?m thick and located at various depths into the target. Highly Ordered Pyrolytic Graphite Crystal (HOPG) was used to obtain the X-ray spectra generated by the interaction of the laser pulse with the solid targets. The experimental results will be presented and the modeling will be discussed. This work was performed under the auspices of U.S. Department of Energy by The University of California, Lawrence Livermore National Laboratory under Contract No. W-7405-Eng-48. Some of this work was undertaken as part of a United Kingdom university collaboration funded by CCLRC.

Akli, Kramer; Freeman, R.; Stephens, R.; Norreys, P.; Beg, F.; Stoeckel, C.

2005-10-01

387

Use of shorted coaxial transmission line for high-power microwave measurement.  

PubMed

In order to reduce the effective area of the receiving antenna to receive microwave power in the high electric field regions, a 1.76 GHz shorted coaxial transmission line (SCTL) is investigated numerically and experimentally in this paper. When the frequency is 1.76 GHz, the simulation results show that the general gain and the effective area of the SCTL are -10.21 dBi and 2.19 cm(2), respectively, and the power capacity of the SCTL is about 41 kW. So the maximum power flow density, which can be measured by the SCTL, is 18.7 kW/cm(2). With the frequency varying from 1.70 to 1.80 GHz, the general gain increases from -11.19 to -9.42 dBi linearly. The general gain of the SCTL is calibrated with the Agilent E8363B network analyzer in an anechoic chamber, and the calibrated results agree with the simulation. The high-power tests are performed on an improved magnetically insulated transmission line oscillator. Compared to the cutoff free-field probe, the maximum power flow density, which can be measured by the SCTL, is higher. PMID:19256667

Fan, Yu-Wei; Zhong, Hui-Huang; Shu, Ting; Li, Zhi-Qiang; Zhou, Heng; Zhou, Wei-Hong; Luo, Ling

2009-02-01

388

High power 980 nm laser diode for free space communications at high bitrates  

Microsoft Academic Search

Direct intensity modulation at 3 Gb\\/s is demonstrated with a 980 nm semiconductor laser diode, which is mainly designed for EDFA pumping applications at high power and reliability. Implications of operating conditions on system performance are addressed

Stefan Mohrdiek; Christoph Harder

1998-01-01

389

A 12Pole Narrowband Highly Selective High-Temperature Superconducting Filter for the Application in the Third-Generation Wireless Communications  

Microsoft Academic Search

An ultra-selective high-temperature superconducting bandpass filter was designed and fabricated to satisfy the demands of the third-generation wireless communications. This filter was designed to have 12-pole quasi-elliptic response with 4.68-MHz bandwidth in the third-generation communications band (a fractional bandwidth of 0.0023). Full-wave simulations were conducted by using Sonnet software. A novel, compact, and low radiation resonator with a high-quality (Q)

Shunzhou Li; Jiandong Huang; Qingduan Meng; Liang Sun; Qiang Zhang; Fei Li; Aisheng He; Xueqiang Zhang; Chunguang Li; Hong Li; Yusheng He

2007-01-01

390

Development of a medical record and radiographic image transmission system using a high-speed communication network.  

PubMed

A medical record and radiographic image transmission system has been developed using a high-speed communication network. The databases are designed to store and transmit the data acquired from the scanner. To maximally utilize the communication bandwidth, the medical records and radiographic images are compressed using the G3 facsimile and JPEG coding standard method, respectively. TCP/IP, OOP and Windows-based system software enable a modular design, future expandability, open system interconnectivity, and diverse image manipulation functions. PMID:10384462

Kim, N H; Yoo, S K; Kim, K M; Kang, Y T; Bae, S H; Kim, S R

1998-01-01

391

Measuring communication and social skills in a high security forensic setting using the behavioural status index.  

PubMed

Assessing patient functioning in the areas of communication and social skills is a core area of practice within psychiatric nursing. Difficulties within these areas can often represent the root of a number of presenting problems. Objective assessment can be difficult without a validated assessment schema. The Behavioural Status Index (BSI) offers such a system of baseline assessment and longitudinal monitoring as a basis for treatment, further specialised assessment, or measurement of outcome during and after interventions. This paper introduces some basic theory and describes the function and purpose of the BSI. This is followed by data analysis for the BSI communications and social skills sub-scale. Data were collected, using a repeated measures method by primary nurses, from a sample of 503 individual patients in two high security mental health hospitals. Results are reported for descriptive statistics, and factor analysis; and differences between the independent groups of Mental Health Act 1983 classification, ward dependency and gender. Data trends are indicative of clinically interesting relationships. A distinct factorial structure emerged suggesting groupings of assertive-interpersonal, non-verbal, social-perceptive and para-linguistic behaviours. Results are reported to be underpinning current European studies. PMID:11866029

Woods, P; Reed, V; Collins, M

2001-06-01

392

Proton radiation damage effects on the response of high speed communication avalanche photodiodes  

NASA Astrophysics Data System (ADS)

This paper discusses the radiation dependent characteristics of avalanche photodiodes (APDs). The reliability, of semiconductor detectors, is very dependent on the degradation modes. In this study, we present the main irradiation effects such as the multiplication gain, minority carrier life time, illumination, and radiation damage coefficient. Protons radiation effects, on the model of two different silicon avalanche photodiode structures, has been investigated. The results demonstrate that the model can accurately calculate the internal parameters of the APDs and produce data that can be directly compared with measurements. The fluence effects of 51 MeV proton irradiation, on the photosensitivity and signal to noise ratio, are also investigated. The objective was to analyze the effect depletion region volume and carrier concentration, of the i-region of APDs, on radiation hardness. Moreover, we have investigated, deeply, some of the degradation performance and capabilities of typical APDs, currently used in many communication and sensing systems, over wide range of the affecting parameters. APDs are used in systems that require coherent, and often single mode, light such as high data rate communications and sensing applications. APDs are an attractive receiver choice for low signal applications because their internal gain mechanism can improve signal to noise ratio. Additionally, we have taken into account the harmful effects of proton radiation on the device performance such as signal to noise ratio, bit error rate, gain, sensitivity, device responsitivity and operating efficiency.

Rashed, Ahmed Nabih Zaki; El-Halawany, Mohamed M. E.

2013-01-01

393

Adrenal cortical responses to high-intensity, short rest, resistance exercise in men and women.  

PubMed

Commercial high-intensity, short rest (HI/SR) protocols have been anecdotally postured to be extremely demanding. However, limited prior studies have demonstrated HI/SR protocols to produce hyperreactions in metabolic and adrenal function; thus, the purpose of this study was to evaluate the physiological effects of an acute, high-intensity (75% 1-repetition maximum), short rest resistance exercise protocol. Nine trained men (age: 23.5 ± 3.5 years, height: 172.4 ± 4.0 cm, weight: 77.8 ± 8.8 kg) and 9 trained women (age: 22.9 ± 2.0 years, height: 168.4 ± 9.4 cm, weight: 68.5 ± 10.4 kg) participated in the HI/SR protocol, which consisted of a descending pyramid scheme of back squat, bench press, and deadlift, beginning with 10 repetitions of each, then 9, then 8, and so on until 1 repetition on the final set. Significant time effects were observed in lactate (immediate post [IP], +15, +60) and cortisol (IP, +15, +60) response. Significant sex effects were observed in lactate response (IP, +15) but not in cortisol response. Total work was higher in men and influenced magnitude of increase in lactate but not cortisol. No significant sex differences were noted in time to completion, average relative intensity, heart rate response or rating of perceived exertion scores. Highest lactate (IP men: 17.3 mmol·L(-1); IP women: 13.8 mmol·L(-1)) and cortisol (+15 men: 1,860.2 nmol·L(-1); +15 women: 1,831.7 nmol·L(-1)) values were considerably greater than those produced in typical resistance exercise programs, confirming that relative intensity and rest period length are important factors determining magnitude of metabolic and adrenal stress. Practical applications for the coach include cautious implementation of HI/SR protocols, as long-term sequential use may promote overtraining. A gradual reduction in rest interval length with concurrent gradual increase in intensity should be used to minimize potential negative effects such as nonfunctional overreaching. PMID:22561973

Szivak, Tunde K; Hooper, David R; Dunn-Lewis, Courtenay; Comstock, Brett A; Kupchak, Brian R; Apicella, Jenna M; Saenz, Catherine; Maresh, Carl M; Denegar, Craig R; Kraemer, William J

2013-03-01

394

WISC-IV Profile in High-Functioning Autism Spectrum Disorders: Impaired Processing Speed is Associated with Increased Autism Communication Symptoms and Decreased Adaptive Communication Abilities  

PubMed Central

Changes in the Wechsler Intelligence Scales for Children-IV (WISC-IV) may affect the IQ profile characteristic of autism spectrum disorders (ASD). Moreover, the association of particular component cognitive abilities (unlike overall IQ) with symptomatology and adaptive functioning in ASD remains unclear. This archival study characterizes the WISC-IV IQ profile among 51 high-functioning (IQ>70) children with ASD and correlates WISC-IV performance with ASD and ADHD symptomatology and adaptive functioning. The ASD WISC-IV profile included strengths on Matrix Reasoning and Similarities, weaknesses on Comprehension (which correlated negatively with social symptoms) and the subtests comprising the Processing Speed Index (Coding, Symbol Search). Processing speed task performance correlated negatively with communication symptoms and positively with communication abilities, indicating its importance to functional outcomes in ASD.

Oliveras-Rentas, Rafael E.; Kenworthy, Lauren; Roberson, Richard B.; Martin, Alex; Wallace, Gregory L.

2012-01-01

395

Study on the short circuit transient process and overcurrent protection of Cockcroft-Walton high voltage power supply  

Microsoft Academic Search

It has always been an important and difficult problem for the designer of an intense current Cockcroft-Walton high voltage power supply to quantitatively select appropriate protective resistance so that not only can the power supply be protected reliably once the high voltage output terminal is short circuited but also the negative influence of the protective resistors to the load characteristics

Y. M. Zhang; X. D. Su; H. Su; J. T. Liu; H. Y. Lv; T. L. Su

2006-01-01

396

Generation of a spectrum with high flatness and high bandwidth in a short length of telecom fiber using microchip laser  

NASA Astrophysics Data System (ADS)

In this work, we studied experimentally the generation of a supercontinuum spectrum induced in a piece of standard single-mode fiber using pulses from a microchip laser. For different values of fiber length, we obtained spectra with high flatness in visible and IR regions. The possibility to generate a spectrum with a high flatness and spectral width of more than ˜1100 nm (600 nm to over 1700 nm) in relatively short lengths of telecom fiber (˜57 m), using as the pump pulses with no more than a few kW peak power at a non-zero-dispersion wavelength, is attributed to the peculiar properties of the pulses generated by the pump source. The physical processes leading to the formation of the supercontinuum spectrum were studied by monitoring the growth of the spectrum while increasing the input power. The coupling efficiency between the microchip laser and the telecom fiber helped us obtain a very wide spectrum. This work shows that the use of conventional fiber for supercontinuum generation can be viewed as a cheap and efficient option, in particular for applications like optical metrology, coherence tomography and low noise sources for the characterization of devices.

Hernandez-Garcia, J. C.; Estudillo-Ayala, J. M.; Pottiez, O.; Rojas-Laguna, R.; Mata-Chavez, R. I.; Gonzalez-Garcia, A.

2013-04-01

397

The social construction of communication climate: An analysis of at-risk students in alternative high school  

NASA Astrophysics Data System (ADS)

Alternative high schools affect more potential high school dropouts than any other school or program and are designed to meet the needs of students who have had difficulty in conventional schools. This study examines the communication climate and constructions of caring in an alternative school for at-risk students by using a qualitative analysis grounded in the theoretical perspective of social constructionism. Observations and interviews were conducted over a six month time period. The first two chapters provide a review of literature and a detailed account of the methods used to conduct the study. Chapter Three describes the socially constructed nature of the school and the participants and the dialectical tensions of communication climate revealed from the analysis. The six dialectical tensions of communication climate are: (1) freedom/restraint, (2) disengagement/engagement, (3) personal communication/impersonal communication, (4) disconfirmation/confirmation, (5) equality/inequality, and (6) ambiguity/clarity. Although the school climate is comprised of each of these tensions, the data suggest that the interaction within the majority of classes created some common characteristics of the general communication climate at the school and can be characterized as one of freedom, disengagement, personal communication, disconfirmation, equality, and ambiguity. Chapter Four describes how caring was constructed and communicated. Although some students perceived some teachers as caring about students and about student learning, half of the students interviewed thought they were not learning or not learning much. Finally, Chapter Five provides a summary of the findings and a discussion of the results. The results of this study contribute to an understanding of the social construction of communication climate and caring in general, and within an alternative school for at-risk students, in specific. The results contribute to the understanding of the complexity of the jointly produced nature of communication climate and reveal the potential effect of communication climate and constructions of caring on teachers' instructional methods, teacher and student interaction, and student learning. Such information can aid pragmatically in the development or modification of programs designed to serve at-risk students, and theoretically in the understanding of the co-constructed nature of communication climate.

Souza, Tasha Jean

398

High-dosage short-term corticotrophin therapy in acute asthma  

PubMed Central

The effect of corticotrophin suspended in gelatin in doses varying from 40 to 400 i.u. on the plasma 11-hydroxycorticosteroid response has been investigated in volunteer subjects in order to determine the optimum dose required to produce prolonged and continuous adrenocortical stimulation using this preparation. Increasing the dose of corticotrophin beyond 200 i.u. did not produce a greater intensity or prolongation of adrenocortical stimulation; 300 i.u. corticotrophin in 7·5 ml. of gelatin produced the same effect as 310 i.u. in 1 ml. gelatin. In order to achieve prolonged and continuous adrenal stimulation the optimum dose of corticotrophin would appear to be 200 i.u., which could be suspended in 1 ml. of gelatin for ease of administration, and which produced adrenal stimulation for approximately 36 hours. The effect of the administration of a single large dose of corticotrophin has been investigated in 13 asthmatic patients during an exacerbation. All had failed to respond to conventional therapy but responded to corticotrophin with one exception. Five patients required no more than two injections for a sustained remission. Seven were discharged needing prolonged corticotrophin in conventional doses. The advatage of using this form of corticotrophin therapy over a short course of high-dosage corticosteroid therapy is discussed.

Glick, I. W.; Friedman, M.

1969-01-01

399

Propagation of High-Intensity Short-Pulse Laser in Overdense Plasmas  

NASA Astrophysics Data System (ADS)

The nonlinear propagation of two high-intensity short-pulse lasers of circular polarization in a foil target is investigated. These two laser pulses illuminate on the left and right sides of the target respectively. Let the vetor potential a=a0 e^i?, There are two constants M=partial _? ?(?^2-1) and W=[(partial_? ?)^2+M^2]/(?^2-1)-?^2+2N_i?, where Ni is the ion density and ?^2=a_0^2+1. The relation of these two constants is found for M=0 andM neq 0. With the help of these two constants and boundary conditions, some interesting results are found. If the foil is sufficiently thin and these laser pulses are very intense, when one laser pulse is intense than another, the first laser pulse will propagate through the foil and the second will reflect. Especially, in the absence of one laser pulse, when another laser pulse is intense enough, the laser pulse will propagate through the target as observed by D. Giulietti et al. [Phys. Rev. Lett. 79,3194(1997)].

Shen, Baifei; Yu, Wei; Xu, Zhizhan

1998-11-01

400

High-fidelity rotor gap measurements in a short-duration turbine rig  

NASA Astrophysics Data System (ADS)

The distance between the tip of rotating airfoils and the stationary casing, i.e., the tip clearance, is a vital parameter to characterize turbomachinery performance. The larger the tip clearance, the lower the turbine efficiency due to the increased loss associated with the hot jet flowing through the gap without generating work. Following the increasing demands in efficiency, these small clearances must be surveyed to avoid mechanical rubbing. The appropriate design of control systems to adjust these small clearances requires a constant monitoring during the whole engine envelope. This paper describes the complete implementation of a high-frequency capacitive sensor on the shroud of a large transonic turbine stage. The presented system and data analysis procedure allow the accurate measurement of the tip clearance of each rotating airfoil. The measurement system performances are first assessed in a simplified test bench and uncertainty analysis is provided. The technique is demonstrated in an aero-propulsion turbine, tested in a short duration rig. The turbine facility has running times of less than 0.5 s, characterized by temperature and rotor speed transients, which requires particular in-situ sensor calibrations. Extensive running tip clearance measurements of the large aero-engine turbine stage validate the system concept and design.

Lavagnoli, Sergio; Paniagua, Guillermo; Tulkens, Maxime; Steiner, Alexander

2012-02-01

401

Over an octave cascaded Raman scattering in short highly germanium-doped silica fiber.  

PubMed

In this paper, we report on cascaded Raman scattering (RS) in a highly germanium-doped silica fiber (HGDF) pumped by a picosecond pulsed master oscillator power amplifier (MOPA) system at 1064 nm in the normal dispersion regime. Benefited by the higher Raman gain of germanium (GeO2) than silica in the core, the length of the HGDF is only several meters. The broadest output spectrum comprises of 10 orders Raman stokes waves and eventually evolves into a supercontinuum (SC) spanning from 1000 to beyond 2100 nm with an output average power up to Watt scale. To the best of our knowledge, this is the first time to obtain such a broad cascaded RS spectrum in a short length of GeO2-doped step index silica fiber. We also numerically investigate the propagation of picosecond pulses in this HGDF based on the generalized nonlinear Schrödinger equation (GNLSE) which includes most of the dispersive and nonlinear effects, and the simulation results are in fairly good agreement with our experiments. It is believed that the numerical approach adopted in this paper is very beneficial for designing customized cascaded Raman fiber lasers before experimental implementations. PMID:23842385

Yin, Ke; Zhang, Bin; Yang, Weiqiang; Chen, Hongwei; Hou, Jing

2013-07-01

402

Department of Energy Mathematical, Information, and Computational Sciences Division: High Performance Computing and Communications Program  

SciTech Connect

This document is intended to serve two purposes. Its first purpose is that of a program status report of the considerable progress that the Department of Energy (DOE) has made since 1993, the time of the last such report (DOE/ER-0536, The DOE Program in HPCC), toward achieving the goals of the High Performance Computing and Communications (HPCC) Program. The second purpose is that of a summary report of the many research programs administered by the Mathematical, Information, and Computational Sciences (MICS) Division of the Office of Energy Research under the auspices of the HPCC Program and to provide, wherever relevant, easy access to pertinent information about MICS-Division activities via universal resource locators (URLs) on the World Wide Web (WWW).

NONE

1996-11-01

403

Communication: High speed optical investigations of a character of boiling-up onset.  

PubMed

In this communication, we discuss the phenomenon of attainable superheat of liquid and the peculiarities of its release by spontaneous boiling-up. We have combined the apparatus for superheating, namely, bubble chamber, with a high speed micro-optical method for detailed monitoring of the initial stage of boiling-up. In experiments on the isothermal pressure drop, it was found that the boiling-up onset of n-hexane is accompanied by characteristic step signal. The signal has proved to be typical of the heterogeneous character of boiling-up onset in a whole range of superheating degrees. The performance of the method for investigation of the refractive index and density for superheated liquids as functions of temperature and pressure has been revealed. The experimental error is estimated to be 0.1%. PMID:22260557

Gurashkin, A L; Starostin, A A; Ermakov, G V; Skripov, P V

2012-01-14

404

High speed GaN micro-light-emitting diode arrays for data communications  

NASA Astrophysics Data System (ADS)

Micro light-emitting diode (micro-LED) arrays based on an AlInGaN structure have attracted much interest recently as light sources for data communications. Visible light communication (VLC), over free space or plastic optical fibre (POF), has become a very important technique in the role of data transmission. The micro-LEDs which are reported here contain pixels ranging in diameter from 14 to 84?m and can be driven directly using a high speed probe or via complementary metal-oxide semiconductor (CMOS) technology. The CMOS arrays allow for easy, computer control of individual pixels within arrays containing up to 16×16 elements. The micro-LEDs best suited for data transmission have peak emissions of 450nm or 520nm, however various other wavelengths across the visible spectrum can also be used. Optical modulation bandwidths of over 400MHz have been achieved as well as error-free (defined as an error rate of <1x10-10) data transmission using on-off keying (OOK) non-return-to-zero (NRZ) modulation at data rates of over 500Mbit/s over free space. Also, as a step towards a more practical multi-emitter data transmitter, the frequency response of a micro-LED integrated with CMOS circuitry was measured and found to be up to 185MHz. Despite the reduction in bandwidth compared to the bare measurements using a high speed probe, a good compromise is achieved from the additional control available to select each pixel. It has been shown that modulating more than one pixel simultaneously can increase the data rate. As work continues in this area, the aim will be to further increase the data transmission rate by modulating more pixels on a single device to transmit multiple parallel data channels simultaneously.

Watson, Scott; McKendry, Jonathan J. D.; Zhang, Shuailong; Massoubre, David; Rae, Bruce R.; Green, Richard P.; Gu, Erdan; Henderson, Robert K.; Kelly, A. E.; Dawson, Martin D.

2012-10-01

405

Improved Decoding Methods of Visible Light Communication System for ITS Using LED Array and High-Speed Camera  

Microsoft Academic Search

In this paper, we consider visible light communication systems using LED array as a transmitter and high-speed camera as a receiver for Intelligent Transport System (ITS). Previously, we have proposed the hierarchical coding scheme which allocates data to spatial frequency components of the image depending on the priority. This scheme is possible to receive information of the high-priority even if

Toru Nagura; Takaya Yamazato; Masaaki Katayama; Tomohiro Yendo; Toshiaki Fujii; Hiraku Okada

2010-01-01

406

High Performance Computing and Communications: Technology for the National Information Infrastructure. Supplement to the President's Fiscal Year 1995 Budget.  

ERIC Educational Resources Information Center

|The federal High Performance Computing and Communications (HPCC) program was created to accelerate the development of future generations of high performance computers and networks and the use of these resources in the federal government and throughout the American economy. This report describes the HPCC program which is developing computing,…

Office of Science and Technology Policy, Washington, DC. National Science and Technology Council.

407

High peak power single frequency pulses using a short polarization-maintaining phosphate glass fiber with a large core  

Microsoft Academic Search

We report a high power, single frequency 1.5 mum pulsed fiber master oscillator-power amplifier laser source using a large core, polarization-maintaining phosphate glass fiber. The phosphate glass fiber produces high powers with low nonlinearities using high Er-Yb codoping and short length. Using this fiber, we were able to generate single frequency pulses with peak powers up to 51.5 kW. This

M. Leigh; W. Shi; J. Zong; Z. Yao; S. Jiang; N. Peyghambarian

2008-01-01

408

A Psychometric Evaluation of the Career Decision Self-Efficacy Scale-Short Form in Chinese High School Students  

Microsoft Academic Search

This study explores the reliability and validity of the Career Decision Self-Efficacy Scale-Short Form (CDSES-SF) in Chinese high school students. One hundred and eighty-three high school students from a city in northeastern China participated in the study. The results indicate that scores on the CDSES-SF are reliable (internal consistency reliability = .93) with this sample of Chinese high school students.

Nan Zhang Hampton

2006-01-01

409

Highly optimized fourth-order short-time approximation for pathintegrals  

SciTech Connect

We derive a fourth-order short-time approximation for use in imaginary-time path-integral simulations. The short-time approximation converges for all continuous and bounded from below potentials, attains quartic order of convergence for sufficiently smooth potentials, and utilizes statistically independent random variables for its construction. These properties recommend the approximation as a natural replacement of the trapezoidal Trotter-Suzuki approximation for physical systems with continuous distributions.

Predescu, Cristian

2006-10-01

410

Substantial biases in ultra-short read data sets from high-throughput DNA sequencing  

Microsoft Academic Search

Novel sequencing technologies permit the rapid production of large sequence data sets. These tech- nologies are likely to revolutionize genetics and bio- medical research, but a thorough characterization of the ultra-short read output is necessary. We gen- erated and analyzed two Illumina 1G ultra-short read data sets, i.e. 2.8 million 27mer reads from a Beta vulgaris genomic clone and 12.3

Juliane C. Dohm; Claudio Lottaz; Tatiana Borodina; Heinz Himmelbauer

2008-01-01

411

High-data rate laser communication field experiment in the turbulence channel  

NASA Astrophysics Data System (ADS)

At present inter-satellite laser communications have made great success, such as SILEX, TerraSAR-X LCT etc. But satellite to ground laser communications still at the experimental stages because of the atmosphere turbulence channel and the clouds. Once the satellite to ground laser communication technology obtains a breakthrough, the all laser spacebased communication era is coming. In this paper, we suggest a DPSK modulation/self-coherent homodyne reception scheme to overcome the atmosphere turbulence. The key in the scheme lies in the phase error compensation with the external environment change. In our experiment, we use two parallel plates rotating to compensate the phase error. The communication data rate reaches 2.5Gbps in the field experiment. The real time bit error rate was obtained with the variation of the communication channel's turbulence.

Sun, Jianfeng; Zhi, Ya'nan; Lu, Wei; Wang, Lijuan; Dai, Enwen; Liu, Liren

2012-10-01

412

Communication Scheduling.  

National Technical Information Service (NTIS)

The high arithmetic rates of media processing applications require architectures with tens to hundreds of functional units, multiple register files, and explicit interconnect between functional units and register files. Communication scheduling enables sc...

P. Mattson W. J. Dally S. Rixner U. J. Kapasi J. D. Owens

2000-01-01

413

High temperature, short time pasteurization temperatures inversely affect bacterial numbers during refrigerated storage of pasteurized fluid milk  

Microsoft Academic Search

The grade A Pasteurized Milk Ordinance specifies minimum processing conditions of 72°C for at least 15 s for high temperature, short time (HTST) pasteurized milk products. Currently, many US milk-processing plants exceed these minimum requirements for fluid milk products. To test the effect of pasteurization tem- peratures on bacterial numbers in HTST pasteurized milk, 2% fat raw milk was heated

M. L. Ranieri; J. R. Huck; M. Sonnen; D. M. Barbano; K. J. Boor

2009-01-01

414

Visuospatial Short-Term Memory Explains Deficits in Tower Task Planning in High-Functioning Children with Autism Spectrum Disorder  

Microsoft Academic Search

Previous findings on planning abilities in individuals with high-functioning autism spectrum disorder (HFA) are inconsistent. Exploring possible reasons for these mixed findings, the current study investigated the involvement of memory in planning performance in 15 children with HFA and 17 typically developing controls. In addition to planning abilities (measured with the Tower of London), short-term memory and delayed recall for

Katharina Zinke; Eva Fries; Mareike Altgassen; Clemens Kirschbaum; Lucia Dettenborn; Matthias Kliegel

2010-01-01

415

Survey of short-term oral corticosteroid administration by orthopaedic physicians in college and high school athletes  

Microsoft Academic Search

The use of oral corticosteroid (OCS) drugs is advocated because of their potent anti-inflammatory effects. They also possess many potential adverse effects. No study has assessed physician prescribing practices of OCS therapy in high school (HS) or college (COL) athletes. This paper reports the prescribing pat- terns of sports medicine physicians who used short-term OCS therapy and to describe associated

Sudhakar G. Madanagopal; John E. Kovaleski; Albert W. Pearsall

416

THERMAL INACTIVATION OF FOOT-AND-MOUTH DISEASE VIRUS IN MILK USING HIGH-TEMPERATURE SHORT TIME PASTEURIZATION  

Technology Transfer Automated Retrieval System (TEKTRAN)

Previous studies of laboratory simulation of high temperature short time pasteurization (HTST) to eliminate foot-and-mouth disease virus (FMDV) in milk have shown that the virus is not completely inactivated at the legal pasteurization minimum (71.7 deg C/15 sec) but is inactivated in flow apparatus...

417

Numerical study of the short pre-arcing time in high breaking capacity fuses via an enthalpy formulation  

Microsoft Academic Search

In order to study the short pre-arcing time in high breaking capacity (HBC) fuses, we use a mathematical model including the phase change of the fuse-element heating coupled with the Laplace equation for the potential and Ohm's law. The thermal model is based on the enthalpy formulation of the heat equation with a source term representing the Joule heating. For

David Rochette; Rachid Touzani; William Bussière

2007-01-01

418

Pterional-subolfactory Approach for Treatment of High Positioned Anterior Communicating Artery Aneurysms  

PubMed Central

Objective The purpose of this study is to compare the surgical outcomes of pterional-subolfactory approach for the high positioned anterior communicating artery (ACoA) aneurysm with the conventional pterional approach. Methods Between February 2005 and December 2012, 463 ACoA aneurysms were surgically treated in our institution. Forty eight high positioned ACoA aneurysms were treated with pterional-subolfactory or conventional pterional approach. High positioned ACoA aneurysms were defined as aneurysms located higher than 10 mm above the anterior clinoid process. Pterional-subolfactory approach is a procedure including dissection of olfactory tract and resection of the gyrus rectus inferior and medial to the olfactory tract. Thirty-four of the 48 cases were treated with pterional-subolfactory approach and 14 were treated conventionally. Results There were 2 postoperative cerebral infarction with the conventional pterional approach, but none with the pterional-subolfactory approach group (p = 0.026). Postoperative digital subtraction angiography revealed significant remnant aneurysm in the conventional pterional approach group. All patients with unruptured aneurysms had good clinical outcomes with Glasgow outcome score of 5. Among ruptured ACoA aneurysm patients, 2 patients with conventional pterional approach had postoperative cerebral infarctions but permanent neurologic deficit was found in only 1 patient. Three patients treated with the pterional-subolfactory approach, who had preoperative ruptured aneurysms had poor clinical outcomes. The mean operation time for the conventional pterional approach was 58 minutes longer than for the pterional-subolfactory approach (p = 0.001). Conclusion We concluded that pterional-subolfactory approach is highly preferable for cases of high positioned ACoA aneurysm, giving a wide and effective operation view.

Kim, Hyool; Joo, Sung-pil; Moon, Hyung-sik

2013-01-01

419

Evaluation of compressed digital high-definition video transmitted through the NASA communications system  

NASA Astrophysics Data System (ADS)

A series of experiments was conducted over the past three years to prepare NASA for the use of high-definition television. In 1989 and in 1990, HDTV technology was evaluated for potential use in launch operations, real-time image analysis, and media dissemination at the Kennedy Space Center (KSC). Evaluation of camera and lens performance is reported here. In November 1991, an experiment was done at the Johnson Space Center (JSC) to evaluate the quality of HDTV that was digitized, compressed to a 45 Mbps data stream, and transmitted through the NASA communications network. The JSC experiment consisted of back-to-back bench tests of the Alcatel/Telettra high-definition coder/decoder (codec), followed by data transmission through the NASA Shuttle communications simulator, and most importantly, actual transmission through the NASA Tracking and Data Relay Satellite System (TDRSS), with a second satellite hop through a domestic satellite and a fiber-optic link at JSC. Static and dynamic test signals were used to test codec performance as were various types of subjective- test scenes with detail and motion. Included in the subjective material was IMAX film shot in space and transferred directly to high-definition video at 30 frames/second. Static tests highlighted the effects of the 54 MHz sampling rate in the codec. Color reproduction tests showed very little color error, even when transcoding externally from GBR signals. Dynamic test signals characterized the DCT and motion-compensation algorithm. Frame-by-frame analysis showed a small reduction in horizontal resolution, small color errors in fine detail, and reduced horizontal and vertical resolution immediately following transitions, where the effect was almost entirely masked by the transitions. Subjective codec performance on moving images at nominal TDRSS bit-error-rates (BER) was extremely good. The codec designers have done a very good job of leaving out information that is not perceived while including almost all information that is needed. Expert viewers, trained in image analysis, gave excellent ratings to the system at typical TDRSS signal levels.

Beakley, Guy W.; Kohn, Elliott S.

1993-01-01

420

Coaxial-type water load for measuring high voltage, high current and short pulse of a compact Marx system for a high power microwave source  

NASA Astrophysics Data System (ADS)

A coaxial-type water load was used to measure the voltage output from a Marx generator for a high power microwave source. This output had a rise time of 20 ns, a pulse duration of a few hundred ns, and an amplitude up to 500 kV. The design of the coaxial water load showed that it is an ideal resistive divider and can also accurately measure a short pulse. Experiments were performed to test the performance of the Marx generator with the calibrated coaxial water load.

Han, Jaeeun; Kim, Jung-ho; Park, Sang-duck; Yoon, Moohyun; Park, Soo Yong; Choi, Do Won; Shin, Jin Woo; So, Joon Ho

2009-11-01

421

High-performance Optical Receivers Using Conventional Sub-micron CMOS Technology for Optical Communication Applications  

NASA Astrophysics Data System (ADS)

A novel sub-micron total-CMOS common-gate Transimpedance Amplifier (TIA) has been designed for high-speed optical communication applications. This total-CMOS approach has given a tremendous flexibility in optimizing the circuit for high performance. The new design shows superior performance compared to recent common-gate and common-base TIAs. Using conventional 0.8 µm CMOS process parameters, simulations showed a transimpedance gain of 69.0 dB over a 3.5 GHz bandwidth, approaching the technology fT of 10 GHz. The mean input referred noise current density was calculated to be 21.2 pA/Hz0.5 at 3.5 GHz, giving an input optical sensitivity of -20.4 dBm for a BER of 10-9. This allows a data transmission easily at 2.5 Gbps for a NRZ synchronous link. The power consumption is only 44 mW when AC coupled to a 50 ? load. In addition, the TIA was designed to tolerate a relatively wide variation in bias conditions while preserving stability. Moreover, simulations using a 0.6 µm CMOS process showed even lower noise and wider bandwidth now at 6.0 GHz. The new design approaches similar IC designs in Si-bipolar or GaAs technologies. The design is the first reported TIA, which combines such features and using conventional 0.8 µm CMOS transistors with fT = 10 GHz.

Touati, F.; Douss, S.; Elfadil, N.; Nadir, Z.; Suwailam, M. B.; Loulou, M.

422

Study of high temperature antennas for HOPE communication/data processing system, part 4-A  

NASA Astrophysics Data System (ADS)

This report describes design and characteristics of heat-resistant antennas supplied in communication and data processing system of H-2 Orbiting Plane (HOPE). In antenna design, the following were reviewed: (1) mode, number and arrangement of antennas required for system operation and spacecraft; (2) polarization mode of TVTX (Television Transmitter) antenna; (3) high-amplification USB (Upper Side Band) antenna; and (4) extensive coverage of GPSR (Global Positioning System Receiver), C/RT (C Band-Radar Transponder) and USB antenna. For materials composing heat-resistant antenna, thermal characteristics of dissolving silica and mullite were studied to determine thermoconductivity and heat capacity in vacuum. For heat resistance of power supply component, conventional SMA (S-Band Multiple Access) connector available up to 125 C was modified to be able to be used in high temperature, and the performance was evaluated at 200 C. As a result, the modified connector was proved to be available in the range of - 80 to 200 C. On the basis of these results, new connector available up to 300 C is planning to be developed.

1993-10-01

423

Annual Enrollment Report Number of Students Studying Journalism and Mass Communication at All-time High.  

ERIC Educational Resources Information Center

|Finds that journalism and mass communication programs appear to be entering another period of rapid enrollment growth, swept up by overall increases in enrollments at United States universities. Finds that only about four in ten of the journalism and mass communication programs report enrollments by race, suggesting many administrators are not…

Becker, Lee B.; Vlad, Tudor; Huh, Jisu; Prine, Joelle

2001-01-01

424

Adaptive MAC protocol for high-load inter-vehicle communication  

Microsoft Academic Search

We have researched on dynamic media access (MAC) protocol for inter-vehicle communication (IVC) for automated vehicle control system (AVCS). In IVC, since there are no nodes that take care of the synchronization of vehicle communication, it is required for each node to sense media information and send its own vehicle information. Our target issues to be solved are the long

Kentaro Dobashi; Takeshi Takahashi; Hideyoshi Tominaga

2005-01-01

425

Model Driven High-Level Power Estimation of Embedded Operating Systems Communication Services  

Microsoft Academic Search

This paper presents a System level Model Driven Architecture (MDA) approach for power estimation of real time operating system (RTOS) communication and synchronization services at early design phases.The approach integrates the Architecture Analysis and Design Language (AADL) in the design flow. We describe how to extend the language for modeling RTOS communication and synchronization services, and we explain how power

Saadia Dhouib; Eric Senn; Jean-Philippe Diguet; Johann Laurent; Dominique Blouin

2009-01-01

426

High speed RS232 fibre optic communication system for underwater remotely operated vehicles  

Microsoft Academic Search

The design and implementation of a communication system for an underwater remotely operated vehicle (ROV) are presented. The system is assumed to be composed of a remotely operated vehicle driven by a set of seven thrusters, a tethering cable including power supply cables and two fibres for communication (the function of which is to transmit and monitor information) and a

J. N. Lygouras; A. Kapsopoulos; Ph. G. Tsalides

1995-01-01

427

In-orbit measurements of short term attitude and vibrational environment on the Engineering Test Satellite VI using laser communication equipment  

NASA Astrophysics Data System (ADS)

Angular microvibrations of platform jitter on a three-axis attitude-stabilized satellite are measured in space using an onboard laser communication terminal. Stable optical tracking control allows the measurement of relative angular variations from the reference line of sight of the optical link. The tracking accuracy in this measurement is less than 1 (mu) rad rms. The angular variation and the drift rate on the satellite are measured at a sampling rate of 500 Hz, and these data are downlinked to a ground station via a satellite-to-ground optical communication link. The power spectral density of the satellite microvibration is calculated by a Fourier transform analysis. The frequency spectrum of the gimbal mirror's angular variation is also obtained when the coarse tracking control is operational. The rms value agrees with the residual coarse tracking error estimated before launch of the satellite. These results will be useful for the future design of a tracking control loop for optical communication systems.

Toyoshima, Morio; Araki, Kenichi

2001-05-01

428

In-situ short-circuit protection system and method for high-energy electrochemical cells  

DOEpatents

An in-situ thermal management system for an energy storage device. The energy storage device includes a plurality of energy storage cells each being coupled in parallel to common positive and negative connections. Each of the energy storage cells, in accordance with the cell's technology, dimensions, and thermal/electrical properties, is configured to have a ratio of energy content-to-contact surface area such that thermal energy produced by a short-circuit in a particular cell is conducted to a cell adjacent the particular cell so as to prevent the temperature of the particular cell from exceeding a breakdown temperature. In one embodiment, a fuse is coupled in series with each of a number of energy storage cells. The fuses are activated by a current spike capacitively produced by a cell upon occurrence of a short-circuit in the cell, thereby electrically isolating the short-circuited cell from the common positive and negative connections.

Gauthier, Michel (La Prairie, CA); Domroese, Michael K. (South St. Paul, MN); Hoffman, Joseph A. (Minneapolis, MN); Lindeman, David D. (Hudson, WI); Noel, Joseph-Robert-Gaetan (St-Hubert, CA); Radewald, Vern E. (Austin, TX); Rouillard, Jean (Saint-Luc, CA); Rouillard, Roger (Beloeil, CA); Shiota, Toshimi (St. Bruno, CA); Trice, Jennifer L. (Eagan, MN)

2003-04-15

429

In-situ short circuit protection system and method for high-energy electrochemical cells  

DOEpatents

An in-situ thermal management system for an energy storage device. The energy storage device includes a plurality of energy storage cells each being coupled in parallel to common positive and negative connections. Each of the energy storage cells, in accordance with the cell's technology, dimensions, and thermal/electrical properties, is configured to have a ratio of energy content-to-contact surface area such that thermal energy produced by a short-circuit in a particular cell is conducted to a cell adjacent the particular cell so as to prevent the temperature of the particular cell from exceeding a breakdown temperature. In one embodiment, a fuse is coupled in series with each of a number of energy storage cells. The fuses are activated by a current spike capacitively produced by a cell upon occurrence of a short-circuit in the cell, thereby electrically isolating the short-circuited cell from the common positive and negative connections.

Gauthier, Michel (La Prairie, CA); Domroese, Michael K. (South St. Paul, MN); Hoffman, Joseph A. (Minneapolis, MN); Lindeman, David D. (Hudson, WI); Noel, Joseph-Robert-Gaetan (St-Hubert, CA); Radewald, Vern E. (Austin, TX); Rouillard, Jean (Saint-Luc, CA); Rouillard, Roger (Beloeil, CA); Shiota, Toshimi (St. Bruno, CA); Trice, Jennifer L. (Eagan, MN)

2000-01-01

430

Energy-Efficient Multi-Access Technologies for Very-High-Throughput Avionic Millimeter Wave, Wireless Sensor Communication Networks  

Microsoft Academic Search

In this paper, we investigate energy-efficient wireless over fiber access channel and link layer technologies using 60-GHz millimeter-wave (mm-wave) band for avionic very high throughput millimeter-wave sensor communication networks (VHT-MSCNs). An efficient architecture for wireless sensor network employing directional mm-wave wireless access technologies is proposed for systems that require very high throughput, such as high definition video signals, for sensing,

Wei Jian; Arshad Chowdhury; Zhensheng Jia; Claudio I. Estevez; Gee-Kung Chang

2010-01-01

431

Large-amplitude plasma wave generation with a high-intensity short-pulse beat wave  

NASA Astrophysics Data System (ADS)

A short-pulse laser beat wave scheme for advanced particle accelerator applications is examined. A short, intense (3-ps, >1018-W cm-2) two-frequency laser pulse is produced by use of a modified chirped-pulse amplification scheme and is shown to produce relativistic plasma waves during interactions with low-density plasmas. The generation of plasma waves was observed by measurement of forward Raman scattering. Resonance was found to occur at an electron density many times that expected, owing to ponderomotive displacement of plasma within the focal region.

Walton, B.; Najmudin, Z.; Wei, M. S.; Marle, C.; Kingham, R. J.; Krushelnick, K.; Dangor, A. E.; Clarke, R. J.; Poulter, M. J.; Hernandez-Gomez, C.; Hawkes, S.; Neely, D.; Collier, J. L.; Danson, C. N.; Fritzler, S.; Malka, V.

2002-12-01

432

Analysis of high-voltage generator stator windings sudden three-phase short-circuit and loss of excitation fault  

Microsoft Academic Search

Base on a prototype of the 130 kw\\/5 kv high voltage generator, the system simulation model is set up for the generator stator windings suddenly three-phase short-circuit failure and loss of excitation failures. The dynamic simulation compared with experiment on DJ18-1 synchronous generator, it reaches conclusion that the system simulation model is correct. The current of the high-voltage generator stator

Lv Yan-ling; Ge Bao-jun; Li Cui-cui; Tao Da-jun; Zhang Zhi-qiang

2009-01-01

433

Design of an Electro-Optic Modulator for High Speed Communications  

NASA Astrophysics Data System (ADS)

The telecommunications and computer technology industries have been requiring higher communications speeds at all levels for devices, components and interconnected systems. Optical devices and optical interconnections are a viable alternative over other traditional technologies such as copper-based interconnections. Latency reductions can be achieved through the use of optical interconnections. Currently, a particular architecture for optical interconnections is being studied at the University of Colorado at Boulder in the EMT/NANO project, called Broadcast Optical Interconnects for Global Communication in Many-Core Chip Multiprocessor. As with most types of networks, including optical networks, one of the most important components are modulators. Therefore adequate design and fabrication techniques for modulators contribute to higher modulation rates which lead to improve the efficiency and reductions in the latency of the optical network. Electro-optical modulators are presented in this study as an alternative to achieve this end. In recent years, nonlinear optical (NLO) materials have been used for the fabrication of high-speed electro-optical modulators. Polymers doped with chromophores are an alternative among NLO materials because they can develop large electro-optic coefficients and low dielectric constants. These two factors are critical for achieving high-speed modulation rates. These polymer-based electro-optical modulators can be fabricated using standard laboratory techniques, such as polymer spin-coating onto substrates, UV bleaching to achieve a refractive index variation and poling techniques to align the chromophores in cured polymers. The design of the electro-optic modulators require the use of the optical parameters of the materials to be used. Therefore the characterization of these materials is a required previous step. This characterization is performed by the fabrication of chromophores-doped polymer samples and conducting transmission and reflection measurements to obtain the optical density. Then, using the Kramer-Kronig analysis, the refractive index change can be calculated. Another measured parameter is the electro-optic coefficient. After obtaining these optical and electric parameters, they are used as inputs in the Computer Aid Design (CAD) software COMSOL Multiphysics to carry out the simulation of the modes of the waveguide. Finally, an analysis of nanotechnology and nanophotonics in telecommunications can show us how the design of optical devices using NLO materials fits in a much larger technological area. It is important to have an understanding of the industry that this technology is a part of. A roadmap for nanophotonics shows where this technology is going and what kind of technological constraints or needs it can solve.

Espinoza, David

434

Means and method for characterizing high power, ultra short laser pulses in a real time, on line manner  

DOEpatents

An ultra short (<10 ps), high power laser pulse is temporally characterized by a system that uses a physical measurement of a wavefront that has been altered in a known manner. The system includes a first reflection switch to remove a portion of a pulse from a beam of pulses, then includes a second reflection switch, operating in a mode that is opposite to the first reflection switch, to slice off a portion of that removed portion. The sliced portion is then directed to a measuring device for physical measurement. The two reflection switches are arranged with respect to each other and with respect to the beam of ultra short pulses such that physical measurement of the sliced portion is related to the temporal measurement of the ultra short pulse by a geometric or trigonometric relationship. The reflection switches are operated by a control pulse that is directed to impinge on each of the reflection switches at a 90.degree. angle of incidence.

Veligdan, James T. (Manorville, NY)

1994-01-01

435

Short-term outcomes of CyberKnife therapy for advanced high-risk tumors: A report of 160 cases  

PubMed Central

The objective of the present study was to evaluate short-term outcomes of CyberKnife therapy in patients with advanced high-risk tumors. A total of 201 target areas from 341 advanced high-risk tumor lesions in 160 patients were treated with CyberKnife. A prescribed dose of 18–60 Gy to the gross tumor volume was delivered in 1–6 fractions to complete the entire treatment in 1 week. Radiographic studies and clinical examinations were performed at 1- to 3-month follow-up intervals, and the results were compared to outcomes of 160 similar advanced high-risk tumor patients who were treated by conformal radiotherapy (CRT). After CyberKnife therapy, the short-term improvement in the quality of life was significant according to radiographic study, radioimmunoassay and ZPS scores of these patients. The total rates of objective efficacy and alleviation of ascities were as high as 66.88 and 67.90%. The short-term outcomes in our series of patients with advanced high-risk tumors treated with CyberKnife appeared to be better compared to conventional CRT. CyberKnife may be an option for patients with incurable advanced high-risk tumors, although further studies of the long-term outcomes are required to confirm the validity.

WANG, YI-SHAN; WANG, YUAN-YUAN; JIANG, PENG; MA, JIAN-JUN; QU, ZHEN; WANG, XI-LIN; LI, JUN-TI; JIA, XI-FENG

2012-01-01

436

High-Frequency Geoacoustic Inversion of Ambient Noise Data Using Short Arrays  

NASA Astrophysics Data System (ADS)

Ocean ambient noise is generated in many ways such as from winds, rain and shipping. A technique has recently been developed (Harrison and Simons, J. Acoust. Soc. Am, Vol. 112 no. 4, 2002) that uses the vertical directionality of ambient noise to determine seabed properties. It was shown that taking a ratio of upward looking beams to downward produces an estimate of the reflection loss. This technique was applied to data in the 200-1500 Hz band using a 16-m vertical array. Extending this to higher frequencies allows the array length to be substantially shortened and greatly reduces interference from shipping. If array lengths can be reduced to about 1 m then it may be possible to hull-mount or tow such an array from a surface ship or submerged vehicle (e.g. an autonomous underwater vehicle). Although this seems attractive the noise is primarily generated by wind which in turn causes a rough sea-surface and bubbles and these factors combined with increased volume attenuation may degrade this type of reflection loss estimate at high frequencies. In this paper, we examine measured noise data from the October 2003 ElbaEx experiment using a 5.5 in array in the 1-4 kHz frequency band. Results indicate the noise field is predictable with modeling and the ratio of upward looking to downward looking beams produces an approximation to the reflection loss which can be inverted for seabed properties. For short arrays (a 1 m aperture is considered here), the beamforming is not ideal over a broad-band of frequencies. The beams are broadened and this leads to an up/down ratio that does not produce a good estimate of reflection loss. This can be especially problematic at low grazing angles which is the part of the reflection loss curve that is often most important to estimate correctly. Techniques will be presented for mitigating the impact of beamwidth and grating lobes on estimating the seabed properties.

Siderius, Martin; Harrison, Chris

2004-11-01

437

Writing short messages in English: Out-of-school practices of Malaysian high school students  

Microsoft Academic Search

For Malaysian adolescents, writing in English covers various forms and serves a range of purposes. Outside the formal school context, students engage in more personalized forms of writing. This paper examines one such form, namely, the writing of short messages, using a sociocultural perspective of literacy as a social discursive practice that implicates identity construction. This paper draws on a

Kok Eng Tan; Paul W. Richardson

2006-01-01

438

Advances in the analysis of short span railway bridges for high-speed lines  

Microsoft Academic Search

The physical model based on moving constant loads is widely used for the analysis of railway bridges. Nevertheless, the moving loads model is not well suited for the study of short bridges (L?20–25 m) since the results it produces (displacements and accelerations) are much greater than those obtained from more sophisticated ones. In this paper two factors are analysed which

P Museros; M. L Romero; A Poy; E Alarcón

2002-01-01

439

The Influence of Residual and Trace Elements on Hot Shortness and High Temperature Embrittlement  

Microsoft Academic Search

The problems of hot shortness and overheating have beset the metallurgist, forgemaster and smith for a surprisingly long time. In recent years the increase in electric steelmaking has emphasized the difficulties arising from the steady build up of residual elements which is the inexorable consequence of scrap recirculation. Although many of the early investigations considered the influence of individual trace

D. A. Melford

1980-01-01

440

Short exposure of albumin to high concentrations of malondialdehyde does not mimic physiological conditions.  

PubMed

Malondialdehyde (MDA), a major lipid peroxidation product, spontaneously binds to, and modifies proteins. In vivo, proteins are physiologically exposed to micromolar MDA concentrations for long periods. In order to mimic this process in vitro, protein modification is often performed by short exposure to millimolar MDA concentrations, also in order to generate antigenic structures for antibody production. However, in our study, spectrophotometric and fluorimetric characteristics, electrophoretic migration, susceptibility to trypsin digestion and reactivity to antibodies indicated substantial differences between albumin incubated with millimolar MDA concentrations for a short period of time and albumin incubated with micromolar MDA concentrations for a long period of time. Therefore, our study showed that short incubation of albumin with millimolar MDA concentrations does not mimic the consequences of albumin exposure to long incubation with micromolar MDA concentrations. This casts doubts on the real possibility that antibodies, elicited with proteins modified with millimolar MDA concentrations for a short period, could detect all MDA-modified proteins in vivo. Moreover, natural antibodies against albumin, modified with micromolar MDA concentrations, have been detected in the serum of healthy blood donors, which appears to justify the existence of these kinds of modified proteins in vivo. PMID:22771309

Millanta, Susanna; Furfaro, Anna Lisa; Carlier, Paolo; Tasso, Bruno; Nitti, Mariapaola; Domenicotti, Cinzia; Odetti, Patrizio; Pronzato, Maria Adelaide; Traverso, Nicola

2012-07-04

441

High yields of olefins and hydrogen from decane in short contact time reactors: rhodium versus platinum  

Microsoft Academic Search

The partial oxidation of n-decane to produce H2, ethylene, and ?-olefins has been compared over Rh and Pt in autothermal reactors at short contact times. Over Rh it is shown that the addition of an alumina wash coat and small foam pore size give higher H2 selectivity (>85%), while the absence of wash coat and larger pore size give more

Jakob J Krummenacher; Lanny D Schmidt

2004-01-01

442

The Discursive Co-Construction of Knowledge, Identity, and Difference: An Ethnography of Communication in the High School Mainstream.  

ERIC Educational Resources Information Center

|Describes the ethnography of communication as a viable, context- and culture-sensitive method for conducting research on classroom discourse. Provides an overview of the method and its role in applied linguistics research and then presents a study of discourse in mainstream high school classes with a large proportion of students who speak English…

Duff, Patricia A.

2002-01-01

443

The high speed buffer board: A SAIL EIA485 communications accelerator card for the vector measuring current meter  

Microsoft Academic Search

A High Speed Buffer Board (HSBB) was developed for the Vector Measuring Current Meter (VMCM) to implement the transmission of data at 9600 baud over an EIA-485 link. The HSBB significantly extends the VMCM communication functionality, which was previously limited to 300 baud transmission via 20mA current loop or FSK telemetry. The increased speed allows rapid sampling of a large

Robin Singer; Douglas M. Butler

1990-01-01

444

Increasing the Involvement of Underrepresented Families in an Urban High School Ninth Grade Through Enhanced Communication and Community Outreach.  

ERIC Educational Resources Information Center

This practicum was designed to develop and implement innovative strategies to improve home/school communication and to increase family involvement of hard-to-reach parents in an effort to cultivate healthy home/school relationships and an open and friendly school climate resulting in a more effective high school. The writer established an advisory…

Gallagher, Dennis P.

445

High-Frequency Wireless Communications System: 2.45-GHz Front-End Circuit and System Integration  

ERIC Educational Resources Information Center

|In this article, a course on high-frequency wireless communications systems is presented. With the 145-MHz baseband subsystem available from a prerequisite course, the present course emphasizes the design and implementation of the 2.45-GHz front-end subsystem as well as system integration issues. In this curriculum, the 2.45-GHz front-end…

Chen, M.-H.; Huang, M.-C.; Ting, Y.-C.; Chen, H.-H.; Li, T.-L.

2010-01-01

446

Toward new generation of the high data rate in-door communication systems-system and key RF technologies  

Microsoft Academic Search

A vision of future high data rate in-door communication systems is presented. The key technological requirements and possible solutions for RF technologies are outlined. The integration of the front end with the antenna in the MM-wave range and incorporation of dual frequency operation, may provide a major step towards a low cost solution. The key technology features are verified by

A. Nesic; V. Brankovic; G. Oberschmidt; T. Dolle; I. Radnovic; D. Krupezevic

1999-01-01

447

Final Report and Documentation for the Optical Backplane/Interconnect for High Speed Communication LDRD  

SciTech Connect

Current copper backplane technology has reached the technical limits of clock speed and width for systems requiring multiple boards. Currently, bus technology such as VME and PCI (types of buses) will face severe limitations are the bus speed approaches 100 MHz. At this speed, the physical length limit of an unterminated bus is barely three inches. Terminating the bus enables much higher clock rates but at drastically higher power cost. Sandia has developed high bandwidth parallel optical interconnects that can provide over 40 Gbps throughput between circuit boards in a system. Based on Sandia's unique VCSEL (Vertical Cavity Surface Emitting Laser) technology, these devices are compatible with CMOS (Complementary Metal Oxide Semiconductor) chips and have single channel bandwidth in excess of 20 GHz. In this project, we are researching the use of this interconnect scheme as the physical layer of a greater ATM (Asynchronous Transfer Mode) based backplane. There are several advantages to this technology including small board space, lower power and non-contact communication. This technology is also easily expandable to meet future bandwidth requirements in excess of 160 Gbps sometimes referred to as UTOPIA 6. ATM over optical backplane will enable automatic switching of wide high-speed circuits between boards in a system. In the first year we developed integrated VCSELs and receivers, identified fiber ribbon based interconnect scheme and a high level architecture. In the second year, we implemented the physical layer in the form of a PCI computer peripheral card. A description of future work including super computer networking deployment and protocol processing is included.

ROBERTSON, PERRY J.; CHEN, HELEN Y.; BRANDT, JAMES M.; SULLIVAN, CHARLES T.; PIERSON, LYNDON G.; WITZKE, EDWARD L.; GASS, KARL

2001-03-01

448

Novel high-sensitivity CE-PTHPT for optical fiber communication  

NASA Astrophysics Data System (ADS)

Planar punch through heterojunction phototransistors with a novel emitter control electrode and ion- implanted isolation (CE-PTHPT) are investigated. The phototransistors have a working voltage of 3-10V and high sensitivity at low input power. The base of the transistor is completely depleted under operating condition. Base current is zero. The CEí*PTHPT has an increased speed and a decreased noise. The novel CE-PTHPT has been fabricated in this paper. The optical gain of GaAlAs/GaAs CE-PTHPT for the incident light power 1.3 and 43nw with the wavelength of 0.8ª+m reached 1260 and 8108. The input noise current calculated is 5.46*10^-16 A/Hz^1/2. For polysilicon emitter CE-PTHPT, the optical gain is 3083 at the input power of 0.174ª+w. The optical gain of InGaAs/InP CE-PTHPT reaches 350 for an incident power of 0.3ª+w at the wavelength of 1.55ª+m. The CE-PTHPT detectors is promising as photo detectors for optical fiber communication system.

Li, Guohui; Yang, Ru; Han, Dejun; Ji, Chengzhou; Du, Shucheng; Zhu, Eenjun; Zeng, YiPing; Zhou, Junming

2001-10-01

449

Effective Communication Between a MicroVAX and a Specialized High-Speed Subprocessor.  

National Technical Information Service (NTIS)

Designing a software system that provides effective communication between two processors requires consideration of many factors. For this project, these factors are divided into two fundamental groups: system requirements; and experimental requirements. T...

H. D. Sweely H. Wang

1988-01-01

450

Performance of the Communication Enhancement and Protective System (CEPS) Under Sustained High and Low Temperatures.  

National Technical Information Service (NTIS)

The USAARL conducted airworthiness testing on the Communication Enhancement and Protection System (CEPS). The test plan included conducting acoustic performance evaluations of the CEPS to determine if the CEPS would maintains clear and audible communicati...

A. J. Houtsma E. Gordon

2008-01-01

451

Corrosion fatigue short crack growth behaviour in a high strength steel  

Microsoft Academic Search

The influence of an aggressive environment (0.6 M, aerated NaCl solution) on short fatigue crack initiation and growth behaviour has been studied. The study involved three major test series, namely: air fatigue, corrosion fatigue, and intermittent air fatigue\\/corrosion fatigue. The above tests carried out under fully reversed torsional loading conditions at a frequency of 5 Hz, showed that it was

G. Murtaza; R. Akid

1996-01-01

452

Transportable optical ground station for high-speed free-space laser communication  

NASA Astrophysics Data System (ADS)

Near real-time data downlinks from aircrafts, satellites and high altitude platforms via high-speed laser commu- nication links is an important research topic at the Institute of Communications and Navigation of the German Aerospace Center (DLR). Ground stations for such scenarios are usually fixed at a certain location. With a mo- tivation to provide a ground station that is quickly and easily deployed anywhere in the world, a transportable optical ground station (TOGS) has been developed. TOGS features a pneumatically deployable Cassegrain-type telescope with main mirror diameter of 60 cm, including optical tracking and receiving system. For calibration of position and attitude, multiple sensors like dual-antenna GPS and inclination sensors have been installed. In order to realize these systems, robust software that operates and controls them is essential. The software is platform independent and is aimed to be used on both mobile and ground terminals. It includes implementa- tion of accurate pointing, acquisition and tracking algorithms, hardware drivers, and user interfaces. Important modules of the software are GPS tracking, optical tracking, star- and satellite tracking, and calibration of the TOGS itself. Recently, a first successful data-downlink from an aircraft to TOGS using GPS tracking has been performed. To streamline the software development and testing process, some simulation environments like mount simulator, aircraft path simulator, tracking camera simulator and tracking error analysis tool have also been developed. This paper presents the overall hardware/software structure of the TOGS, and gives results of the tracking accuracy improvement techniques like GPS extrapolation and optical tracking.

Shrestha, Amita; Brechtelsbauer, Martin

2012-10-01

453

Against expectation: a short sequence with high signal elucidates cone snail phylogeny.  

PubMed

A short (259 nucleotide) conserved intronic sequence (CIS) is surprisingly informative for delineating deep phylogenetic relationships in cone snails. Conus species previously have been assigned to clades based on the evidence from mitochondrial 12S and 16S rRNA gene sequences (1129 bp). Despite their length, these genes lack the phylogenetic information necessary to resolve the relationships among the clades. Here we show that the relationships can be inferred from just 46 sites in the very short CIS sequence (a portion of "intron 9" of the ?-glutamyl carboxylase gene). This is counterintuitive because in short sequences sampling error (noise) often drowns out phylogenetic signal. The intron 9 CIS is rich in synapomorphies that define the divergence patterns among eight clades of worm- and fish-hunting Conus, and it contains almost no homoplasy. Parsimony, maximum likelihood and Bayesian analyses of the combined sequences (mt rRNA+CIS) confirm most of the relationships among 23 Conus sequences. This phylogeny implies that fish-hunting behavior evolved at least twice during the history of Conus-once among New World species and independently in the Indo-Pacific clades. PMID:21147238

Kraus, Nicole J; Corneli, Patrice Showers; Watkins, Maren; Bandyopadhyay, Pradip K; Seger, Jon; Olivera, Baldomero M

2010-12-13

454

Short?term changes in the blood leucocyte and platelet count following different durations of high?intensity treadmill running  

Microsoft Academic Search

Short?term changes in the blood leucocyte count after exercise are known to be dependent on the intensity of exercise performed. The aim of the present study was to investigate the effects of the duration of high?intensity exercise on changes in the leucocyte and platelet count during the early recovery period. On separate occasions following a standard warm?up, eight healthy subjects

Michael Gleeson; Andrew K. Blannin; Dean A. Sewell; Robert Cave

1995-01-01

455

Short-Term Vegetation Dynamics of Alnus Dominated Peatlands: a High Resolution Palaeoecological Case Study from Western Pomerania (NE Germany)  

Microsoft Academic Search

Actual ecological research postulates for alder carrs a cyclic alternation of Alnus tree vegetation with open fen or Salix dominated vegetation. Such cycles are also indicated in palaeo-ecological studies, but normally the temporal resolution of\\u000a these studies is insufficient to resolve the duration of short-term cycles in vegetation development. This paper presents\\u000a a high resolution palaeoecological study (including pollen, macrofossils

Alexandra Barthelmes; Dörthe Gerloff; Pim de Klerk; Hans Joosten

2010-01-01

456

High-dose erythropoietin has no effect on short- or long-term graft function following deceased donor kidney transplantation  

Microsoft Academic Search

We evaluated short- and long-term effects of high-dose recombinant human erythropoietin (rHuEPO) in kidney transplantation in a prospective double-blind, placebo-controlled study. Patients with chronic kidney disease following receipt of a deceased donor kidney allograft were randomized to 3 doses of 40,000 units rHuEPO or placebo. The primary study end point was kidney function 6 weeks after transplantation with secondary end

Carsten Hafer; Thomas Becker; Jan T Kielstein; Elisabeth Bahlmann; Anke Schwarz; Nikolai Grinzoff; Daria Drzymala; Isabelle Bonnard; Nicolas Richter; Frank Lehner; Juergen Klempnauer; Hermann Haller; Jana Traeder; Danilo Fliser

2012-01-01

457

Effect of honey high-temperature short-time heating on parameters related to quality, crystallisation phenomena and fungal inhibition  

Microsoft Academic Search

The effect of a unique high-temperature short-time heating treatment on natural honeys to produce both a fungi inhibition and a crystallisation delay simultaneously was evaluated. As responses to treatments, hydroxymethylfurfural content, diastase activity, fungi and yeast development, and crystallisation starting time were measured. Besides, moisture, fructose, glucose and acidity were determined.Heating can produce a decrease in honey quality, which is

E. A. Tosi; E. Ré; H. Lucero; L. Bulacio

2004-01-01

458

Effect of High-Temperature Short-Time Treatment of Wheat Flour on Gluten Vitality and Structure  

Microsoft Academic Search

Cereal Chem. 73(3):375-378 The effect of high-temperature short-time (HTST) applications on changes in the extrinsic fluorescence (8-aniline-l-naphthalene sulfonate gluten in its natural flour environment was investigated. Changes occur- (ANS) binding) revealed enhanced surface hydrophobicity, which how- ring in HTST-treated samples during storage and in samples subjected to ever, regressed on storage. Consistent with these observations was the severe thermal denaturation

NICOLETTA GUERRIERI; PAOLO CERLETTI

459

MODERATE RESISTANCE TRAINING VOLUME PRODUCES MORE FAVORABLE STRENGTH GAINS THAN HIGH OR LOW VOLUMES DURING A SHORT TERM TRAINING CYCLE  

Microsoft Academic Search

Gonzalez-Badillo, J.J., E.M. Gorostiaga, R. Arellano, and M. Izquierdo. Moderate resistance training volume produces more favorable strength gains than high or low volumes during a short-term training cycle. J. Strength Cond. Res. 19(3):689- 697. 2005.—The purpose of this study was to examine the effects of 3 resistance training volumes on maximal strength in the snatch (Sn), clean & jerk (C&J),

JUAN J. GONZALEZ-BADILLO; ESTEBAN M. GOROSTIAGA; RAUL ARELLANO; MIKEL IZQUIERDO

460

Ascorbic acid degradation kinetics in mushrooms in a high-temperature short-time process controlled by a thermoresistometer  

Microsoft Academic Search

The degradation of ascorbic acid was studied in mushrooms heated at temperatures between 110 and 140°C, high-temperature short-time conditions, in a five-channel computer-controlled thermoresistometer. The kinetics parameters were calculated on the assumption that there are 2 degradation mechanisms, one aerobic (during the first few seconds of the process) and the other anaerobic. The 2 stages followed first-order reaction kinetics, with

R Blasco; M. J Esteve; A Fr??gola; M Rodrigo

2004-01-01

461

Topoisomerase 1 provokes the formation of short deletions in repeated sequences upon high transcription in Saccharomyces cerevisiae  

PubMed Central

High transcription is associated with genetic instability, notably increased spontaneous mutation rates, which is a phenomenon termed Transcription-Associated-Mutagenesis (TAM). In this study, we investigated TAM using the chromosomal CAN1 gene under the transcriptional control of two strong and inducible promoters (pGAL1 and pTET) in Saccharomyces cerevisiae. Both pTET- and pGAL1-driven high transcription at the CAN1 gene result in enhanced spontaneous mutation rates. Comparison of both promoters reveals differences in the type of mutagenesis, except for short (?2 and ?3 nt) deletions, which depend only on the level of transcription. This mutation type, characteristic of TAM, is sequence dependent, occurring prefentially at di- and trinucleotides repeats, notably at two mutational hotspots encompassing the same 5?-ACATAT-3? sequence. To explore the mechanisms underlying the formation of short deletions in the course of TAM, we have determined CanR mutation spectra in yeast mutants affected in DNA metabolism. We identified topoisomerase 1-deficient strains (top1?) that specifically abolish the formation of short deletions under high transcription. The rate of the formation of (?2/?3nt) deletions is also reduced in the absence of RAD1 and MUS81 genes, involved in the repair of Top1p–DNA covalent complex. Furthermore ChIP analysis reveals an enrichment of trapped Top1p in the CAN1 ORF under high transcription. We propose a model, in which the repair of trapped Top1p–DNA complexes provokes the formation of short deletion in S. cerevisiae. This study reveals unavoidable conflicts between Top1p and the transcriptional machinery and their potential impact on genome stability.

Takahashi, Tomio; Burguiere-Slezak, Guenaelle; Van der Kemp, Patricia Auffret; Boiteux, Serge

2011-01-01

462

New scheme for high-efficiency operation of PWM inverter-driven hysteresis motor with short-duration overexcitation  

Microsoft Academic Search

This paper presents the new scheme for high-efficiency operation of PWM inverter-driven hysteresis motor with short-duration overexcitation. When the terminal voltage Vi of the hysteresis motor running at synchronous speed is continuously increased up to nVi (n > 1) and then continuously decreased to Vi, input currents are reduced and output power is increased at the same time. Because of

Tomotsugu Kubota; Takahiro Tamura; Kazumi Kurihara

2010-01-01

463

High-sensitivity, large dynamic range, auto-calibration methane optical sensor using a short confocal Fabry–Perot cavity  

Microsoft Academic Search

We present a methane sensor based on a short confocal Fabry–Perot cavity. The sensor uses not only the transmitted signals from the back cavity mirror to obtain high sensitivity but also the reflected signals from the front cavity mirror to extend efficient dynamic range and to cancel emitter-amplitude variations. Thus a minimum detectable absorbance of 4.1×10?5 has been achieved and

Lei Dong; Wangbao Yin; Weiguang Ma; Lei Zhang; Suotang Jia

2007-01-01

464

High-Resolution DNA Melt Curve Analysis of the Clustered, Regularly Interspaced Short-Palindromic-Repeat Locus of Campylobacter jejuni  

Microsoft Academic Search

A novel method for genotyping the clustered, regularly interspaced short-palindromic-repeat (CRISPR) locus of Campylobacter jejuni is described. Following real-time PCR, CRISPR products were subjected to high-resolution melt (HRM) analysis, a new technology that allows precise melt profile determination of amplicons. This investigation shows that the CRISPR HRM assay provides a powerful addition to existing C. jejuni genotyping methods and emphasizes

Erin P. Price; Helen Smith; Flavia Huygens; Philip M. Giffard

2007-01-01

465

Vegetation response to a short interval between high-severity wildfires in a mixed-evergreen forest  

Microsoft Academic Search

Summary 1. Variations in disturbance regime strongly influence ecosystem structure and function. A prominent form of such variation is when multiple high-severity wildfires occur in rapid succession (i.e. short-interval (SI) severe fires, or 're-burns'). These events have been proposed as key mechanisms altering successional rates and pathways. 2. We utilized a natural experiment afforded by two overlapping wildfires occurring within

Daniel C. Donato; Joseph B. Fontaine; W. Douglas Robinson; J. Boone Kauffman; Beverly E. Law

2009-01-01

466

Space weather effects on airline communications in the high latitude regions  

NASA Astrophysics Data System (ADS)

In the polar regions, ground-based VHF facilities for air-traffic control are lacking (and non-existent on the Russian side of the pole) and satellite communication systems either not available or expensive to retrofit to current aircraft and hence there remains a need for HF communication systems. Unfortunately, at these latitudes space weather can significantly affect the propagation of HF radio signals and the forecasting techniques currently employed by the airline industry are somewhat crude. In this paper, a new project that aims to provide forecasting of HF propagation characteristics for use by civilian airlines operating over polar routes will be described and preliminary results presented. Previous work in this area [e.g. Stocker et al., 2007] has focussed on taking HF signal measurements (e.g. SNR, delay and Doppler spread, and direction of arrival) on a limited number of propagation paths and developing an ionospheric model that incorporates high latitude features (e.g. polar patches and arcs) which, when combined with raytracing, allows the broad characteristics of the observations to be reproduced [Warrington et al., 2012]. The new project will greatly extend this work and consists of a number of stages. Firstly, HF measurements from an extensive network of purpose built transmitters and receivers spanning the Arctic regions will be collected and analysed. In order to test a wide variety of scenarios, the propagation paths will have different characteristics, e.g. different lengths and covering different parts of the northern ionosphere (i.e. polar cap paths where both terminals are in the polar cap, trans-auroral paths, and sub-auroral paths) and observations will be taken at a range of HF frequencies for a period covering the current (so far weak) solar maximum and part of the declining phase. Simultaneously, high latitude absorption measurements utilising the Global Riometer Array (GLORIA) will be collected and analysed. Next, the observations of the signal characteristics (i.e. both reflection and absorption properties) will be related to prevailing space weather parameters. Following on from this, an auroral absorption prediction model based on solar wind and interplanetary data will be developed together with the further refinement of the existing ionospheric model taking into account the new observations and adding auroral and polar cap absorption models. Algorithms for nowcasting and forecasting of radio propagation conditions for trans-polar aircraft will then be developed from the ionospheric model. In addition to the approach described above, the benefits of ground station diversity using both the experimental data and the models developed during the project will also be investigated. Stocker A.J., E.M. Warrington, and D.R. Siddle, Comparison between the measured and predicted parameters of HF radio signals propagating along the mid-latitude trough and within the polar cap, Radio Science, 42, RS3019, doi:10.1029/2006RS003557, 2007. Warrington EM, Zaalov NY, Stocker AJ, Naylor JS, HF propagation modelling within the polar ionosphere, Radio Science, 47, Article number RS0L13, doi:10.1029/2011RS004909, 2012.

Stocker, Alan; Siddle, Dave; Warrington, Mike; Honary, Farideh; Zaalov, Nikolay; Homam, Mariyam; Boteler, David; Danskin, Donald; de Franceschi, Georgiana; Ascaneus, Svend

2013-04-01

467

Spectral mirror for ultra-short, high peak power, multi-PW Ti:sapphire lasers  

NASA Astrophysics Data System (ADS)

A multilayer mirror for spectral filtering adapted to ultra-short and multi-PW Ti:Sa laser has been designed, manufactured and characterized. The method used to determine both the reflectivity shape and the coating design leads to global compensation of gain narrowing, saturation and spectral phase. The result is a spectral control on 200 nm range while keeping a flat spectral phase. This kind of filter will enable obtaining 15 fs pulse duration for multi-PW