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1

Congestion game model for efficient utilization of spectrum  

NASA Astrophysics Data System (ADS)

Dynamic spectrum access is a way of gaining access to individual frequencies on a temporary basis. This makes use of the frequency assigned to a specific user (primary user) by using specific devices and/or spectrum management techniques. The spectrum management techniques can be done by allocating the spectrum (a) through auctions (market based), (b) using management techniques (c) spectrum sharing (detects and utilizes the unutilized part of the spectrum) (d) command and control, and (e) through opportunistic spectrum access. In opportunistic spectrum access, the secondary or unlicensed user transfers the data with high speed and at short distances with tolerable interference (without disturbing) to the primary signal. Efficient spectrum allocation techniques were discussed using stochastic models, economic models, genetic algorithms, and optimization techniques. The existing models need to be tuned for better performance with optimum utilization of the power. In this paper, we proposed a model that provides access with tolerable interference from secondary users to the primary users while maximizing the spectrum utilization. Furthermore, we designed a congestion game model for efficient utilization of the spectrum by secondary users with minimum interference to primary users. The simulation results show that the congestion game model helps to utilize the spectrum efficiently.

Reddy, Y. B.; Smith, Heather

2010-04-01

2

Efficient spectrum utilization in mobile radio communication systems  

NASA Astrophysics Data System (ADS)

The problem of efficient spectrum utilization in mobile radio communication systems is addressed. A frequency channel assignment algorithm is proposed and studied by computer simulations for applications to mobile telephone systems and combined mobile telephone and dispatch systems. Spectrum efficient modulation techniques, namely, Duobinary Coded MSK and TFM are studied for the application of data transmission via mobile radio. The performance of coherent and noncoherent detections is studied under the mobile radio environments. The probability of error is calculated for both discriminator detection and differential detection. The steady state phase error probability of a digital phase locked loop with a phase step input is calculated under the fast fading mobile radio environments.

Elnoubi, S. M.

1980-03-01

3

Detecting Primary Signals for Efficient Utilization of Spectrum Using Q- Learning (POSTPRINT).  

National Technical Information Service (NTIS)

The efficient utilization of underutilized spectrum is the main theme of the current research. The cognitive radio with the help of Q-learning algorithm is used to detect the presence of primary signals and make utilize the spectrum in the absence of prim...

Y. Reddy

2010-01-01

4

Improving VHF Spectrum Utilization  

NASA Technical Reports Server (NTRS)

Limited VHF communications system capacity and increasing air traffic results in congestion of the aviation VHF spectrum. The voice communications errors and delayed channel access create system congestion and air traffic delays. Regulatory subdivision of bands for specific functions limits flexibility in the frequency usage. The objective of this viewgraph presentation is to identify near/mid/far term technologies to improve the performance and spectrum efficiency of current and emerging VHF communications systems. Select technologies with the highest potential, perform research and development to bring them to implementation stage.

Andro, Monty; Orr, Richard; Foore, Larry; Sheehe, Charles; Freeman, Mark; Nguyen, Thanh; Bretmersky, Steven; Laberge, Chuck; Buchanan, David

2004-01-01

5

Efficient Spectrum Utilization by Time Division Beam Control Scheme in Cellular Systems  

Microsoft Academic Search

In order to realize broadband data services and to cope with a huge number of users, high system capacity will become an important issue for future multimedia mobile communication systems beyond the IMT-2000 system. As an efficient technique focusing on this purpose, this paper proposes a new radio access method that introduces a time division beam control technique to the

Masaharu HATA; Shigeru TOMISATO; Hitoshi YOSHINO

6

High efficiency laser spectrum conditioner  

DOEpatents

A high efficiency laser spectrum conditioner for generating a collinear parallel output beam containing a predetermined set of frequencies from a multifrequency laser. A diffraction grating and spherical mirror are used in combination, to disperse the various frequencies of the input laser beam and direct these frequencies along various parallel lines spatially separated from one another to an apertured mask. Selection of the desired frequencies is accomplished by placement of apertures at locations on the mask where the desired frequencies intersect the mask. A recollimated parallel output beam with the desired set of frequencies is subsequently generated utilizing a mirror and grating matched and geometrically aligned in the same manner as the input grating and mirror.

Greiner, Norman R. (Los Alamos, NM) [Los Alamos, NM

1980-01-01

7

Spectrum-orbit utilization - An overview. [domestic satellite communication systems  

NASA Technical Reports Server (NTRS)

This paper discusses the problems associated with the efficient utilization of the natural resources of frequency spectrum and geo-stationary orbital arc. The nature of these resources is explained and their quantities are estimated. The present and projected future demand for them is given, and the problem areas are identified and discussed. Special emphasis is placed on mutual interference, launch limitations, propagation effects, and operational restrictions. The technical factors bearing on these problems, such as antenna patterns, modulation methods, emission restrictions, equipment characteristics, and system requirements, are discussed in detail. Some important trade-offs are presented, and special techniques that can be used to increase spectrum-orbit utilization are described. Particular emphasis is given throughout to U.S. domestic satellite communication systems.

Sawitz, P. H.

1975-01-01

8

Validity and utility of bipolar spectrum models.  

PubMed

The bipolar spectrum model suggests that several patient presentations not currently recognized by the DSM warrant consideration as part of a mood disorders continuum. These include hypomania or mania associated with antidepressants; manic symptoms which fall short of the current DSM threshold for hypomania; and depression attended by multiple non-manic markers that are associated with bipolar course. Evidence supporting the inclusion of these groups within the realm of bipolar disorder (BP) is examined. Several diagnostic tools for detecting and characterizing these patient groups are described. Finally, options for altering DSM-IV criteria to allow some of the above patient presentations to be recognized as bipolar are considered. More data on the validity and utility of these alterations would be useful, but limited changes appear warranted now. We describe an additional BP Not Otherwise Specified (BP NOS) example which creates a subthreshold hypomanic analogue to cyclothymia, consistent with existing BP NOS criteria. This change should be accompanied by additional requirements for the assessment and reporting of non-manic bipolar markers. PMID:18199236

Phelps, James; Angst, Jules; Katzow, Jacob; Sadler, John

2008-02-01

9

Cutoff wavelength optimization for high-efficiency split spectrum photovoltaics  

NASA Astrophysics Data System (ADS)

Split spectrum photovoltaics, where incident light is divided onto multiple cells on the basis of wavelength, are an exciting recent development in the solar energy field. This technology has the potential to exceed record conversion efficiencies by utilizing a large number of p-n junctions while mitigating the constraints that plague monolithic cells: lattice matching and current matching. Each cell in a split spectrum system can have a different lattice constant (allowing for more combinations of materials) and to have different operating currents (allowing for more combinations of band spacing). In this work, we examine a split spectrum system utilizing a single spectrum splitting device (a dichroic filter) to divide the solar spectrum onto two cells. Whereas many split spectrum designs use numerous filters to direct light onto single junction cells, in this system each cell is composed of multiple active junctions. Each cell is then tailored to absorb a portion of the solar spectrum. The combination of the two cells allows for four, five, or more active junctions while maintaining lattice and current matching conditions in each cell. A number of different cutoff frequencies for the dichroic filter are examined. Each cutoff frequency corresponds to its own combination of ideal band placements for both the shorter and longer wavelength cells. Materials corresponding to those band placements are examined to determine if any combinations can satisfy lattice matching parameters; designs which do are then simulated using TCAD Sentaurus.

Downs, Chandler; Vandervelde, Thomas E.

2014-03-01

10

Land Mobile Spectrum Utilization: Detroit, Michigan.  

National Technical Information Service (NTIS)

The report describes the extent of radio frequency utilization by FCC licensees in the Private Land Mobile Radio Services in the Detroit metropolitan area. Radio users in these services include among others: police and fire departments, hospitals, public ...

L. D. Reed K. A. Larson W. V. Tranavitch

1978-01-01

11

The effects of geography on spectrum-orbit utilization  

NASA Technical Reports Server (NTRS)

With over forty satellites in geostationary orbit, and many more planned, it is becoming increasingly difficult to find suitable orbit positions for new systems operating at 4 and 6 GHz. Efficient spectrum-orbit utilization can be achieved with frequency-reuse techniques - orthogonal polarization, earth-station antenna discrimination, and satellite antenna discrimination - provided that service-area geography is considered. Service arc - that portion of the orbit which affords useful service to all points in a given area - is a function of the area's climate, terrain, and location as well as its size and shape. Of the three techniques, satellite antenna discrimination is the most sensitive to these factors. According to the BSS (broadcasting-satellite service) antenna reference pattern, the maximum discrimination possible is the on-axis gain, which can be as high as 49 dB for a beamwidth of 0.6 degrees, or as low as 32 dB for a 3.5-degree beamwidth. Unlike the Fixed-Satellite Service (FSS), the BSS will normally have beams that cover no more than one or two time zones.

Sawitz, P. H.

1979-01-01

12

Planning satellite communication services and spectrum-orbit utilization  

NASA Technical Reports Server (NTRS)

The relationship between approaches to planning satellite communication services and spectrum-orbit utilization is considered, with emphasis on the fixed-satellite and the broadcasting-satellite services. It is noted that there are several possible approaches to planning space services, differing principally in the rigidity with which technical parameters are prescribed, in the time for which a plan remains in force, and in the procedures adopted for implementation and modifications. With some planning approaches, spectrum-orbit utilization is fixed at the time the plan is made. Others provide for greater flexibility by making it possible to postpone some decisions on technical parameters. In addition, the two political questions of what is equitable access and how it can be guaranteed in practice play an important role.

Sawitz, P. H.

1982-01-01

13

Efficient Spectrum Sensing With Dyadic Tree Partitioning  

Microsoft Academic Search

A low-complexity spectrum-sensing method that is based on dyadic (binary) tree partitioning is proposed. For this purpose, first, a representation of the spectrum occupation with a dyadic tree is developed. Then, the accuracy of this representation is evaluated through a rate-distortion criterion. Using this criterion, a pruning algorithm for the dyadic tree that minimizes the number of sensing operations for

Lionel Gueguen; Berna Sayrac

2010-01-01

14

Energy efficient new homes programs: Utility experiences  

Microsoft Academic Search

In 1986, the Bonneville Power Administration and many Pacific Northwest utilities embarked on an unparalleled effort to encourage the construction of new homes in the BPA region that go beyond current levels of space heating energy efficiency. By 1995, regional power plans call for 85% of new, electrically space heated homes to be built to these levels, termed the Model

J. W. Callaway; K. R. Branch

1987-01-01

15

The 24 benefits of energy efficiency to electric utilities  

Microsoft Academic Search

While electric utilities in the United States brace themselves for a more competitive era, many advocates of energy efficiency are concerned that such an era may exclude utilities` new-found emphasis on energy efficiency programs. Utilities are ``right-sizing`` (cutting staff) and reducing their operating budgets in every way possible to stabilize if not lower their rates... all as a means of

Flanigan

1995-01-01

16

Spectrum\\/Orbit Utilization Program for Geostationary Satellites  

Microsoft Academic Search

Mutual interferences among geostationary satellite communication systems determine the permitted spacing between satellites and the limits on the capacity of the orbit\\/spectrum resources available. This paper describes the \\

Edward F. Miller

1984-01-01

17

75 FR 70725 - Spectrum Policy Seminar for the Utility Sector  

Federal Register 2010, 2011, 2012, 2013

...Communications Requirements of Smart Grid Technologies. '' The complete text...issues arising from the deployment of smart grid technologies, can be found at...surely play in the deployment of smart grid technologies. At this spectrum...

2010-11-18

18

Land mobile spectrum utilization: San Francisco, California and Chicago, Illinois  

NASA Astrophysics Data System (ADS)

Radio frequency utilization by Federal Communication Commission licenses in the San Francisco and Chicago urbanized areas is described. The license include among others: police and fire departments; hospitals; public utilities; marine; and common carrier users. The extent of frequency utilization is described in terms of four occupancy categorizations (zero, low, substantial and very high). The rationale for these categories and their relationship to measured usage data is given. Summary tables enable direct comparison of the use by various individual, radio services, e.g., police, business, taxicab, etc. Separate analyses are given for utilization by each of the land mobile radio services and for each frequency band.

Reed, L. D.

1980-08-01

19

Economics and utility energy-efficiency programs: Energy-efficient manufactured housing.  

National Technical Information Service (NTIS)

As utilities investigate ways to implement conservation programs, the differences between customer and utility economic perspectives become more important. Because utilities bear the cost of new energy sources, energy efficiency investments that are cost-...

A. D. Lee S. A. Onisko

1992-01-01

20

Spectrum\\/orbit utilization program for geostationary satellites  

Microsoft Academic Search

Mutual interferences among geostationary satellite communication systems determine the permitted spacing between satellites and the limits on the capacity of the orbit\\/spectrum resources available. This paper describes the computer program for analyzing the mutual interferences among communication satellite systems. Capabilities of the program are described. Inputs, models used, program operations, and program outputs are given. To show application of the

E. F. Miller

1984-01-01

21

Land Mobile Spectrum Utilization: New York, New York.  

National Technical Information Service (NTIS)

The report describes the extent of radio frequency utilization by FCC licensees in the Private Land Mobile Radio Services in the New York metropolitan area. Radio users in these services include among others: police and fire departments, hospitals, public...

L. D. Reed W. V. Tranavitch K. A. Larson

1979-01-01

22

Pulse Interference Cancelling System for Spread Spectrum Signals Utilizing Active Coherent Detection.  

National Technical Information Service (NTIS)

Disclosed is a pulse interference cancelling system for spread spectrum signals utilized in a digital noise coded communications system. The system includes a first and second noise coded signal channel located in a noise coded signal receiver which also ...

F. S. Gutleber

1982-01-01

23

Hybrid tandem solar cell for concurrently converting light and heat energy with utilization of full solar spectrum  

Microsoft Academic Search

A two-compartment hybrid tandem cell comprising a dye-sensitized solar cell as top cell and a thermoelectric cell as bottom cell has been developed to increase the overall photovoltaic conversion efficiency by utilization of full solar spectrum. The photovoltaic properties of the four-wire and two-wire hybrid tandem cells have been characterized and the working principle has been demonstrated using the electron

Xiao-Zhi Guo; Yi-Duo Zhang; Da Qin; Yan-Hong Luo; Dong-Mei Li; Yu-Tong Pang; Qing-Bo Meng

2010-01-01

24

Energy-Efficient Cooperative Spectrum Sensing by Optimal Scheduling in Sensor-Aided Cognitive Radio Networks  

Microsoft Academic Search

A promising technology that tackles the conflict between spectrum scarcity and underutilization is cognitive radio (CR), of which spectrum sensing is one of the most important functionalities. The use of dedicated sensors is an emerging service for spectrum sensing, where multiple sensors perform cooperative spectrum sensing. However, due to the energy constraint of battery-powered sensors, energy efficiency arises as a

Ruilong Deng; Jiming Chen; Chau Yuen; Peng Cheng; Youxian Sun

2012-01-01

25

Slurry Utilization Efficiency Studies in Chemical Mechanical Planarization  

NASA Astrophysics Data System (ADS)

The residence time distribution of slurry in the pad-wafer interface was experimentally determined and used to calculate the slurry utilization efficiency (?) of the chemical mechanical planarization (CMP) process. Slurry utilization efficiency represents the percentage of slurry that actually participates in the polish by entering the region bounded between the wafer and the pad. Results show that ? ranges from 2 to 22%, depending on operating conditions such as applied wafer pressure, relative pad wafer velocity, slurry flow rate and pad surface texture (i.e. type of pad grooving).

Philipossian, Ara; Mitchell, Erin

2003-12-01

26

Manganese influx and its utilization efficiency in wheat.  

PubMed

Manganese deficiency in wheat has become an important nutritional disorder particularly in alkaline calcareous soils where rice-wheat rotation is followed. This experiment was aimed to study the mechanism of Mn efficiency during various developmental stages in six wheat cultivars grown at two Mn levels viz. 0 and 50 mg Mn kg(-1) soil (Mnapplied as MnSO4 x H20) in pots. The Mn vegetative efficiency calculated on the basis of shoot dry weight at anthesis indicated HD 2967 and PBW 550 (bread wheat) as Mn efficient and durums as Mn inefficient. The efficient cultivars recorded highest values for influx, uptake, shoot dry weight, leaf area/plant, SPAD index, F(v)/F(m)ratio and root length that explained their higher efficiencies whereas inefficiency of durum cultivars was attributed to their smaller roots and lower influx. Under Mn deficiency, PDW 314 and PDW 291 retained 68% and 64%, respectively, of total Mn uptake in vegetative parts (stem and leaves) and lowest in grains 7% and 5%, respectively, whereas PBW 550, BW 9178 and HD 2967 retained 29, 37 and 34% in vegetative parts, and 21, 17 and 15 % in grains, respectively at maturity. Higher utilization efficiency of efficient genotypes also indicated that increased Mn uptake with Mn supply produced more efficiently grains in efficient genotypes but vegetative parts in inefficient genotypes. Hence Mn efficiency of a cultivar could be explained by longer roots, higher uptake, influx and efficiency index during vegetative phase and higher grain yield and utilization efficiency during generative phase. PMID:24956896

Jhanji, Shalini; Sadana, Upkar Singh; Shankar, Arun; Shukla, Arvind Kumar

2014-06-01

27

Implementation of a shaped beam model in Spectrum Orbit Utilization Program (SOUP)  

Microsoft Academic Search

Using elliptical beam models the mutual interference among all DBS (direct broadcast satellite) systems within a region can be calculated using a software package called SOUP (Spectrum Orbit Utilization Program). The authors discuss the addition of a shaped beam model to this software. This software has been used extensively for the DirecTv Direct Broadcast Satellite system for the United States.

B. Williams; P. Ramanujam; J. Meyers

1993-01-01

28

Utility investments in low-income-energy-efficiency programs  

SciTech Connect

The objective of this study is to describe the energy-efficiency programs being operated by utilities for low-income customers. The study focuses, in particular, on programs that install major residential weatherization measures free-of-charge to low-income households. A survey was mailed to a targeted list of 600 utility program managers. Follow-up telephone calls were made to key non- respondents, and a random sample of other non-respondents also was contacted. Completed surveys were received from 180 utilities, 95 of which provided information on one or more of their 1992 low-income energy-efficiency programs for a total of 132 individual programs. These 132 utility programs spent a total of $140.6 million in 1992. This represents 27% of the total program resources available to weatherize the dwellings of low-income households in that year. Both the total funding and the number of programs has grown by 29% since 1989. A majority of the 132 programs are concentrated in a few regions of the country (California, the Pacific Northwest, the Upper Midwest, and the Northeast). Although a majority of the programs are funded by electric utilities, gas utilities have a significantly greater average expenditure per participant ($864 vs. $307 per participant). The most common primary goal of low-income energy-efficiency programs operating in 1992 was {open_quotes}to make energy services more affordable to low-income customers{close_quotes}. Only 44% of the programs were operated primarily to provide a cost-effective energy resource. Based on a review of household and measure selection criteria, equity and not the efficiency of resource acquisition appears to dominate the design of these programs.

Brown, M.A. [Oak Ridge National Lab., TN (United States); Beyer, M.A. [Aspen Systems Corp., Oak Ridge, TN (United States); Eisenberg, J.; Power, M. [Economic Opportunity Research Institute, Washington, DC (United States); Lapsa, E.J. [Manhattan Data Systems, Knoxville, TN (United States)

1994-09-01

29

Frequency adaptation efficiency of spread spectrum communications under narrowband interference  

NASA Astrophysics Data System (ADS)

We investigate a new possibility of frequency adaptation for spread spectrum communication systems. A special index is introduced to characterize the adaptation gain referring to the nonadaptive case. An existence of frequency band limit is developed for the allocated frequency band for possible frequency maneuver. The investigation method can be adapted both to direct sequence and frequency hopping spread spectrum techniques. In the paper only the narrowband interference case is treated

Goot, R. E.; Gavan, J.

2003-10-01

30

Network efficiency in autism spectrum disorder and its relation to brain overgrowth.  

PubMed

A substantial body of evidence links differences in brain size to differences in brain organization. We have hypothesized that the developmental aspect of this relation plays a role in autism spectrum disorder (ASD), a neurodevelopmental disorder which involves abnormalities in brain growth. Children with ASD have abnormally large brains by the second year of life, and for several years thereafter their brain size can be multiple standard deviations above the norm. The greater conduction delays and cellular costs presumably associated with the longer long-distance connections in these larger brains is thought to influence developmental processes, giving rise to an altered brain organization with less communication between spatially distant regions. This has been supported by computational models and by findings linking greater intra-cranial volume, an index of maximum brain-size during development, to reduced inter-hemispheric connectivity in individuals with ASD. In this paper, we further assess this hypothesis via a whole-brain analysis of network efficiency. We utilize diffusion tractography to estimate the strength and length of the connections between all pairs of cortical regions. We compute the efficiency of communication between each network node and all others, and within local neighborhoods; we then assess the relation of these measures to intra-cranial volume, and the differences in these measures between adults with autism and typical controls. Intra-cranial volume is shown to be inversely related to efficiency for wide-spread regions of cortex. Moreover, the spatial patterns of reductions in efficiency in autism bear a striking resemblance to the regional relationships between efficiency and intra-cranial volume, particularly for local efficiency. The results thus provide further support for the hypothesized link between brain overgrowth in children with autism and the efficiency of the organization of the brain in adults with autism. PMID:24368901

Lewis, John D; Theilmann, Rebecca J; Townsend, Jeanne; Evans, Alan C

2013-01-01

31

Spectrum governance regimes: efficiency properties and policy choices  

Microsoft Academic Search

Purpose – This paper proposes to describe a model and the results of a simulation exercise used to compare welfare outcomes for four governance regimes that might be employed for wireless services: two spectrum ownership regimes and two open commons regimes. Aims also to examine practical implications for policy makers. Design\\/methodology\\/approach – A formal economic model was constructed and computational

Steven S. Wildman; Johannes M. Bauer; Carol Ting

2006-01-01

32

Limitations in substrate utilization efficiency by Zymomonas mobilis  

Microsoft Academic Search

Optimal growth conditions for Zymomonas mobilis have been established using continuous cultivation methods. Optimal substrate utilization efficiency occurs with 2.5 g l-1 yeast extract, 2.0 g l-1 ammonium sulfate and 6.0 g l-1 magnesium sulfate in the media. Catabolic activity is at its maximum with glucose uptake rates of 16–18 g l-1 h-1 and ethanol production rates of 8–9 g

Sue Cromie; Horst W. Doelle

1982-01-01

33

An increase of utilization efficiency of X-ray beam  

NASA Astrophysics Data System (ADS)

The features of absorbed dose field formation in objects irradiated with scanned X-ray beams at double—and four-sided irradiation were investigated both analytically and by Monte Carlo methods. An analytical approach uses an angular/spectrum X-ray characteristics calculated with PENELOPE, JEANT 4 and ModeXR codes. It was shown that the special angular orientation of electron beam incidence on the X-ray converter leads to X-ray dose smoothing on the surface of the irradiated object. At the same time, a double-sided irradiation can provide high X-ray beam efficiency at dose uniformity ration (DUR) <1.5 for sizeable object thickness. At four-sided irradiation, the angular orientation of electron beam incidence on the X-ray converter should be changed so as to focus the electrons to the center of the converter. At this mode X-ray beam efficiency is more than 60%.

Lazurik, V. T.; Pismenesky, S. A.; Popov, G. F.; Rudychev, D. V.; Rudychev, V. G.

2007-11-01

34

Development of a gas leak detection method based on infrared spectrum imaging utilizing microbolometer camera  

NASA Astrophysics Data System (ADS)

Development of an early gas leak detection system is essential for safety of energy storage tank fields or chemical plants. Contact-type conventional gas sensors are not suitable for remote surveillance of gas leakage in wide area. Infrared camera has been utilized for gas leak detection, however it is limited only for detecting particular gas. In this study a gas leak identification system, which enables us to detect gas leakage and to identify gas type and density, is developed based on infrared spectrum imaging system utilizing low cost and compact microbolometer infrared camera. Feasibility of the proposed system was demonstrated by experimental results on identification of hydrofluorocarbon gas.

Sakagami, Takahide; Anzai, Hiroaki; Kubo, Shiro

2011-05-01

35

Efficient population utilization strategy for particle swarm optimizer.  

PubMed

The particle swarm optimizer (PSO) is a population-based optimization technique that can be applied to a wide range of problems. This paper presents a variation on the traditional PSO algorithm, called the efficient population utilization strategy for PSO (EPUS-PSO), adopting a population manager to significantly improve the efficiency of PSO. This is achieved by using variable particles in swarms to enhance the searching ability and drive particles more efficiently. Moreover, sharing principals are constructed to stop particles from falling into the local minimum and make the global optimal solution easier found by particles. Experiments were conducted on unimodal and multimodal test functions such as Quadric, Griewanks, Rastrigin, Ackley, and Weierstrass, with and without coordinate rotation. The results show good performance of the EPUS-PSO in solving most benchmark problems as compared to other recent variants of the PSO. PMID:19095550

Hsieh, Sheng-Ta; Sun, Tsung-Ying; Liu, Chan-Cheng; Tsai, Shang-Jeng

2009-04-01

36

Economics and utility energy-efficiency programs: Energy-efficient manufactured housing  

SciTech Connect

As utilities investigate ways to implement conservation programs, the differences between customer and utility economic perspectives become more important. Because utilities bear the cost of new energy sources, energy efficiency investments that are cost-effective to them may not be cost-effective to their customers who pay average energy prices and have different economic parameters. The Bonneville Power Administration (BPA) and other parties in the Pacific Northwest have initiated an innovative manufactured (mobile) home energy conservation program. Because manufactured homes are regulated by the Department of Housing and Urban Development (HUD), are exempt from local regulations, and comprise up to 50% of new housing starts in some parts of the United States, utilities and energy planners need to find creative ways to make the economics of manufactured housing energy-efficiency investments more attractive. Differences between the economic criteria and perspectives of consumers and utilities can be used to design energy-efficiency programs. This paper discusses life-cycle cost (LCC) analysis as a framework for highlighting these differences and examines other economic criteria. It then presents information from the Pacific Northwest manufactured housing program to illustrate the application of this framework to a real-world program. Findings from this program should,be of interest to utility and government planners who are designing innovative energy-efficiency programs.

Lee, A.D.; Onisko, S.A.

1992-10-01

37

A combined irradiance-transmittance solar spectrum and its application to photovoltaic efficiency calculations.  

PubMed

SOLTRAN is a flexible computer model for the direct solar beam intensity spectrum at the earth's surface. It has been derived by combining the extra-terrestrial solar spectrum with the atmospheric transmittance spectrum. Application of SOLTRAN to the calculation of the potential efficiency of photovoltaic cells demonstrates the effect of atmospheric absorption bands. These bands prevent unequivocal assignment of optimum energy gap values. PMID:17839483

Ireland, P J; Wagner, S; Kazmerski, L L; Hulstrom, R L

1979-05-11

38

Distributed energy efficient spectrum access in cognitive radio wireless ad hoc networks  

Microsoft Academic Search

In this paper, energy efficient spectrum access is considered for a wireless cognitive radio ad hoc network, where each node is equipped with cognitive radio, has limited energy, and the network is an OFDMA system operating on time slots. In each slot, the users with new traffic demand will sense the spectrum and locate the available subcarrier set. Given the

Song Gao; Lijun Qian; Dhadesugoor R. Vaman

2009-01-01

39

Efficient parallel FIR filter implementations using frequency spectrum characteristics  

Microsoft Academic Search

Parallel (or block) FIR digital filters can be used either for high-speed or low-power (with reduced supply voltage) applications. Traditional parallel filter implementations cause linear increase in the hardware cost with respect to the block size. Recently, an efficient parallel FIR filter implementation technique requiring a less-than linear increase in the hardware cost was proposed. This paper makes two contributions.

Jin-Gyun Chungl; Yong-Bae Kim; Hang-Geun Jeong; Keshab K. Parhi; Zhongfeng Wang

1998-01-01

40

Direct-Sequence Spread-Spectrum Modulation for Utility Packet Transmission in Underwater Acoustic Communication Networks  

NASA Astrophysics Data System (ADS)

This thesis investigates the feasibility and performance of using Direct-Sequence Spread-Spectrum (DSSS) modulation for utility-packet transmission in Seaweb underwater wireless acoustic communications networks, Seaweb networks require robust channel-tolerant utility packets having a low probability of detection (LPD) and allowing for multi-user access, MATLAB code simulated the DSSS transmitter and receiver structures and a modeled channel impulse response represented the underwater environment, The specific modulation scheme implemented is direct-sequence, differentially encoded binary phase-shift keying (DS-DBPSK) with quadrature spreading, Performance is examined using Monte Carlo simulation Bit error rates and packet error rates for various signal-to-noise ratios and channel conditions are presented and the use of a RAKE receiver, forward error-correction coding and symbol interleaving are examined for improving system performance.

Duke, Peter S.

2002-09-01

41

Design of high-resolution and multilevel reference pattern for improvement of both light utilization efficiency and signal-to-noise ratio in coaxial holographic data storage.  

PubMed

A high-resolution and multilevel designed reference pattern (DRP) is presented for improvement of both light utilization efficiency and the signal-to-noise ratio (SNR) of reconstructed images in coaxial holographic data storage. With a DRP, the desired Fourier power spectrum of a reference beam is obtained. Numerical and experimental results show that the DRP increases the SNR compared with that of a random phase mask (RPM). Moreover, the light utilization efficiency of the DRP is higher than that of a high-resolution RPM. In addition, the effect of the phase level and the pixel pitch of DRPs on the SNR and the light utilization efficiency are investigated. PMID:24921144

Nobukawa, Teruyoshi; Nomura, Takanori

2014-06-10

42

Efficient fission neutron spectrum matrix representation by singular value decomposition technique  

Microsoft Academic Search

In order to treat efficiently a huge fission neutron spectrum (FNS) matrix in a criticality calculation, the singular value decomposition (SVD) technique is introduced to an FNS matrix representation. The required number of SVD components for reconstruction of an FNS matrix is expected to be small since an incident neutron energy dependence of FNS is not so significant. The proposed

Go Chiba; Akio Yamamoto; Masashi Tsuji; Tadashi Narabayashi

2012-01-01

43

Transport Capacity and Spectrum Efficiency of Large Wireless CDMA Ad Hoc Networks with Retransmission Diversity  

Microsoft Academic Search

In this paper, we study the transport capacity in packet-meters per slot per node and the space time spectrum efficiency in bit-meters per Hz per second per square meter for large wireless CDMA ad hoc networks, considering optimization of MAC and routing protocols and fixed physical layer. The node density and processing gain tend to infinity with their ratio kept

Yi Sun

44

Modifying the solar spectrum to enhance silicon solar cell efficiency—An overview of available materials  

Microsoft Academic Search

There are three ways in which the cell efficiency of silicon solar cells may be improved by better exploitation of the solar spectrum: down-conversion (cutting one high energy photon into two low energy photons), photoluminescence (shifting photons into wavelength regions better accepted by the solar cell) and up-conversion (combining low energy photons to one high energy photon). In this paper,

C. Strümpel; M. McCann; G. Beaucarne; V. Arkhipov; A. Slaoui; V. Švr?ek; C. del Cañizo; I. Tobias

2007-01-01

45

Protein requirements and ageing: metabolic demand and efficiency of utilization.  

PubMed

The protein requirements of the elderly were investigated with [13C]leucine balance studies of metabolic demand, the efficiency of postprandial protein utilization (PPU) and the consequent apparent protein requirement. Ten elderly subjects aged 68-91 years (five men and five women) and ten young adult subjects aged 21-31 years (five men and five women) were infused with L-[1-13C]leucine for 9 h commencing in the postabsorptive state (0-3 h), continuing during the half-hourly feeding of low-protein meals (LP; protein 3% energy, 3-6 h), and during similar feeding of isoenergetic higher protein meals (HP; protein 15% energy, 6-9 h). Leucine oxidation and balance were determined from plasma [1-13C]-alpha-ketoisocaproate enrichment and expired 13CO2 excretion measured during the 3rd hour of each 3 h period. The protein intake during the HP phase was similar to the habitual intake estimated in the subjects from 24 h urinary N excretion. Metabolic demand was defined as equal to twice the body-protein equivalent of measured postabsorptive leucine oxidation. The efficiency of PPU was calculated from the increased leucine oxidation observed during feeding, and the apparent protein requirement was defined as metabolic demand/PPU and calculated in relation to both body weight (BW) and fat-free mass (FFM) determined by densitometry or bioimpedance. Metabolic demand in the young adults was 0.83 g protein/kg per d; in both elderly groups it was 36% lower when expressed per kg BW and 30% lower when expressed per kg FFM. The apparent protein requirement calculated from metabolic demand and PPU was 0.99 g protein/kg per d in the young adults and this was also lower in the elderly, although this was only significant in the men (0.66 g per kg BW, P = 0.013; 0.79 g per kg FFM, P = 0.02). The results show that in this group of healthy elderly adults protein requirements as assessed from leucine balance studies were either similar to or less than those of younger adults. PMID:9175990

Fereday, A; Gibson, N R; Cox, M; Pacy, P J; Millward, D J

1997-05-01

46

Lateral Spectrum Splitting Concentrator Photovoltaics: Direct Measurement of Component and Submodule Efficiency  

SciTech Connect

To achieve high energy conversion efficiency, a solar module architecture called lateral spectrum splitting concentrator photovoltaics (LSSCPV) is being developed. LSSCPV can concentrate available sunlight and laterally split a single beam into bands with different spectra for absorption by different solar cells with band gaps matched to the split spectrum. Test assemblies of a sample LSSCPV architecture were constructed, each of which contains four p-n junctions and two optical pieces. Independent experiments or simulations had been implemented on the components but by using optimal assumptions. In order to examine the actual performances of all the components, which are dependent on each other and the light source, direct outdoor measurements were made. A set of self-consistent efficiency definitions was articulated and a test bed was developed to measure the parameters required by the efficiency calculation. By comparing the component efficiency items derived from the outdoor measurement and the expected values based on independent simulations, the potential opportunities for efficiency improvement are determined. In the outdoor measurement at the University of Delaware, the optical component demonstrated 89.1% efficiency. Additional assemblies were tested at the National Renewable Energy Laboratory. One assembly demonstrated 36.7% submodule efficiency, which compares favorably with the 32.6% previously reported verified submodule efficiency.

Xiaoting, W.; Waite, N.; Murcia, P.; Emery, K.; Steiner, M.; Kiamilev, F.; Goossen, K.; Honsberg, C.; Barnett, A.

2012-03-01

47

Family-Focused Autism Spectrum Disorder Research: A Review of the Utility of Family Systems Approaches  

ERIC Educational Resources Information Center

A family member with an autism spectrum disorder presents pervasive and bidirectional influences on the entire family system, suggesting a need for family-focused autism spectrum disorder research. While there has been increasing interest in this research area, family-focused autism spectrum disorder research can still be considered relatively…

Cridland, Elizabeth K.; Jones, Sandra C.; Magee, Christopher A.; Caputi, Peter

2014-01-01

48

Assessment of Global Functioning in Adolescents with Autism Spectrum Disorders: Utility of the Developmental Disability-Child Global Assessment Scale  

ERIC Educational Resources Information Center

Assessment of global functioning is an important consideration in treatment outcome research; yet, there is little guidance on its evidence-based assessment for children with autism spectrum disorders. This study investigated the utility and validity of clinician-rated global functioning using the Developmental Disability-Child Global Assessment…

White, Susan W.; Smith, Laura A.; Schry, Amie R.

2014-01-01

49

Indirect measurement of the thermal-acoustic efficiency spectrum of a long turbulent burner  

NASA Technical Reports Server (NTRS)

A new method is described for deducing the thermal-acoustic efficiency spectrum (defined as the fraction of combustion heat release converted to acoustic energy at a given frequency) of a long turbulent burner from the sound spectrum measured in the far field. The method, which is based on a one-dimensional model of the unsteady flow in the burner, is applied to a tubular diffusion-flame hydrogen burner whose length is large compared to its diameter. The results for thermal powers ranging from 4.5 to 22.3 kW show that the thermal-acoustic efficiency is relatively insensitive to the burner power level, decreasing from a value of around 0.0001 at 150 Hz with a slope of about 20 dB per decade. Evidence is presented indicating that acoustic agitation of the flame below 500 Hz, especially in the neighborhood of the resonant frequencies of the burner, is a significant acoustic source.

Mahan, J. R.; Jones, J. D.; Blevins, L. R.; Cline, J. G.

1983-01-01

50

Improving electric power utility efficiency: Issues and recommendations. World Bank technical paper  

SciTech Connect

The volume presents the issues and recommendations that emerged from the Electric Power Utility Efficiency Improvement Study conducted by the World Bank and nine other internatinal technical and financial assistance organizations during 1989-91. The present volume extracts from the main study a set of efficiency guidelines for power utility planners and policymakers emphasizing the objectives of developing the power sector (including appropriate demand-side management) while sustaining the financial/commercial viability of the utilities; rationalizing the organizational and fiscal interactions between utilities and governments; enhancing the utilities' institutional capacity for governance and staff management; structuring utility organizations for operational efficiency; and coordinating utility activities with financing agencies' policies and procedures. A checklist, presented as an annex, provides point-by-point review of quantitative and qualitative factors that can be used to rate the performance of a utility. Quantitative measures are accompanied by target values where appropriate. (Copyright (c) 1994 The International Bank for Reconstruction and Development).

Menke, C.; Fazzari, P.G.

1994-01-01

51

Highly spectrum efficient OFDM\\/PDM wireless networks by using optical SSB modulation  

Microsoft Academic Search

Optical frequency division multiplexing (OFDM) wireless access network using optical single-sideband modulation is proposed, which allows to deliver different wireless signals from a central station to each base station over an optical fiber network. The optical single-sideband (SSB) OFDM can achieve the highest spectrum efficiency of 0.25 b\\/s\\/Hz. A 0.25 b\\/s\\/Hz has been experimentally verified by the error-free transport of

Ken-Ichi Kitayama

1998-01-01

52

Optimization of gas utilization efficiency for short-pulsed electron cyclotron resonance ion source.  

PubMed

Numerical analysis of (6)He atoms utilizing efficiency in the ion source with powerful gyrotron heating is performed in present work using zero-dimensional balanced model of ECR discharge in a magnetic trap. Two ways of creation of ion source with high gas utilization efficiency (up to 60%-90%) are suggested. PMID:22380189

Izotov, I V; Skalyga, V A; Zorin, V G

2012-02-01

53

Molecular Control of Sucrose Utilization in Escherichia coli W, an Efficient Sucrose-Utilizing Strain  

PubMed Central

Sucrose is an industrially important carbon source for microbial fermentation. Sucrose utilization in Escherichia coli, however, is poorly understood, and most industrial strains cannot utilize sucrose. The roles of the chromosomally encoded sucrose catabolism (csc) genes in E. coli W were examined by knockout and overexpression experiments. At low sucrose concentrations, the csc genes are repressed and cells cannot grow. Removal of either the repressor protein (cscR) or the fructokinase (cscK) gene facilitated derepression. Furthermore, combinatorial knockout of cscR and cscK conferred an improved growth rate on low sucrose. The invertase (cscA) and sucrose transporter (cscB) genes are essential for sucrose catabolism in E. coli W, demonstrating that no other genes can provide sucrose transport or inversion activities. However, cscK is not essential for sucrose utilization. Fructose is excreted into the medium by the cscK-knockout strain in the presence of high sucrose, whereas at low sucrose (when carbon availability is limiting), fructose is utilized by the cell. Overexpression of cscA, cscAK, or cscAB could complement the W?cscRKAB knockout mutant or confer growth on a K-12 strain which could not naturally utilize sucrose. However, phenotypic stability and relatively good growth rates were observed in the K-12 strain only when overexpressing cscAB, and full growth rate complementation in W?cscRKAB also required cscAB. Our understanding of sucrose utilization can be used to improve E. coli W and engineer sucrose utilization in strains which do not naturally utilize sucrose, allowing substitution of sucrose for other, less desirable carbon sources in industrial fermentations.

Sabri, Suriana; Nielsen, Lars K.

2013-01-01

54

Health Manpower Planning and Efficient Health Manpower Utilization.  

National Technical Information Service (NTIS)

Research is proposed which would develop a health manpower planning model by providing a link between a microanalytic model of the efficient production of medical services and a model of the regional and national demands for medical care. The purpose of t...

F. L. Golladay M. F. Hansen W. L. Hansen K. R. Smith

1972-01-01

55

Improved Engine Performance and Efficiency Utilizing a Superturbocharger.  

National Technical Information Service (NTIS)

The need for current and future military vehicles to include more powerful and efficient powertrains is critical to both improving operational performance and reducing logistical burden. VanDyne SuperTurbo Inc. is working jointly with TARDEC and OEM partn...

E. VanDyne J. Brown T. Waldron

2012-01-01

56

Optical concentration effects on conversion efficiency of a split-spectrum solar cell system  

NASA Astrophysics Data System (ADS)

A detailed analysis is presented to exhibit the possibility of a split-spectrum solar cell system to improve solar energy conversion above 50% and to explain the important role of optical concentration in such a system. The analysis is based on numerical simulation using a solar cell capacitance simulator. In the analysis, it is assumed that an ideal optical system is used to split the solar spectrum and concentrate the radiation into a six-solar-cell system. The parameters of the assumed and used materials are obtained from literature. The analysis shows that an efficiency of 45.39% can be achieved without concentration. This can reach 47.35% with 10 Sun concentration and 49.84% with 100 Sun concentration.

Hossain, Mohammad I.; Bousselham, Abdelkader; Alharbi, Fahhad H.

2014-02-01

57

Volatilization of mercury compounds and utilization of various aromatic compounds by a broad-spectrum mercury resistant Bacillus pasteurii strain  

SciTech Connect

Aquatic ecosystems may receive aromatic compounds through various routes. These compounds can cause cancerous diseases in aquatic animals and enhance mutagenicity of the sediments. The persistence of aromatic compounds deposited in sediments is affected by microbial degradation. Plasmid-determined mercuric and organomercurial resistance in microorganisms has also been studied by several workers. Utilization of various aromatic compounds as sole sources of carbon by an Hg-resistant bacterial strain has not been reported. The author isolated a broad-spectrum Hg-resistant Bacillus pasteurii strain DR{sub 2} which could volatilize different mercury compounds and utilize various aromatic compounds as sole sources of carbon. This strain preferentially utilized benzene in a medium containing both glucose and benzene. To their knowledge, until recently there has been no report on preferential utilization of other compounds, particularly an aromatic compound to glucose in a mixture.

Pahan, K.; Ray, S.; Gachhui, R.; Chaudhuri, J.; Mandal, A. (Univ. College of Science, Calcutta (India))

1991-04-01

58

Towards the efficient, total glycan utilization of biomass.  

PubMed

From biomass to mass transportation: Waste biomass (newspaper, corn stover, straw, and wood) is converted into biofuel precursors and value-added products in excellent yield using a simple, inexpensive process involving concurrent hydrolysis, dehydration, and substitution reactions in a biphasic reactor. The hemicellulose fraction of these substrates is simultaneously converted into furfural, and together these constitute an efficient means for the total exploitation of the carbohydrate content of biomass. PMID:19408263

Mascal, Mark; Nikitin, Edward B

2009-01-01

59

A compendium of utility-sponsored energy efficiency rebate programs: Final report  

SciTech Connect

Rebate programs are becoming increasingly popular among utilities across the country as a method to persuade customers to purchase more energy efficient appliances, space conditioning systems, lighting products and motors. While there is substantial experience with and interest in utility rebate programs, utilities and other organizations lack comprehensive information on other utility-sponsored energy efficient rebate programs. The authors developed this Compendium to fill that gap. This Compendium contains information on 59 energy efficiency rebate programs, based upon a survey of 157 utilities. The information on each rebate program has been cross-tabulated and analyzed to identify such variables as program characteristics, products included, efficiency levels, rebate amounts, funding levels, energy and peak power savings, and the cost of peak demand reduction. Summary conclusions about these variables are also presented. 16 refs., 25 tabs.

Berman, E.; Cooper, M.; Geller, H.

1987-12-01

60

Spectrum splitting using multi-layer dielectric meta-surfaces for efficient solar energy harvesting  

NASA Astrophysics Data System (ADS)

We designed a high-efficiency dispersive mirror based on multi-layer dielectric meta-surfaces. By replacing the secondary mirror of a dome solar concentrator with this dispersive mirror, the solar concentrator can be converted into a spectrum-splitting photovoltaic system with higher energy harvesting efficiency and potentially lower cost. The meta-surfaces are consisted of high-index contrast gratings (HCG). The structures and parameters of the dispersive mirror (i.e. stacked HCG) are optimized based on finite-difference time-domain and rigorous coupled-wave analysis method. Our numerical study shows that the dispersive mirror can direct light with different wavelengths into different angles in the entire solar spectrum, maintaining very low energy loss. Our approach will not only improve the energy harvesting efficiency, but also lower the cost by using single junction cells instead of multi-layer tandem solar cells. Moreover, this approach has the minimal disruption to the existing solar concentrator infrastructures.

Yao, Yuhan; Liu, He; Wu, Wei

2014-06-01

61

Spectrum splitting using multi-layer dielectric meta-surfaces for efficient solar energy harvesting  

NASA Astrophysics Data System (ADS)

We designed a high-efficiency dispersive mirror based on multi-layer dielectric meta-surfaces. By replacing the secondary mirror of a dome solar concentrator with this dispersive mirror, the solar concentrator can be converted into a spectrum-splitting photovoltaic system with higher energy harvesting efficiency and potentially lower cost. The meta-surfaces are consisted of high-index contrast gratings (HCG). The structures and parameters of the dispersive mirror (i.e. stacked HCG) are optimized based on finite-difference time-domain and rigorous coupled-wave analysis method. Our numerical study shows that the dispersive mirror can direct light with different wavelengths into different angles in the entire solar spectrum, maintaining very low energy loss. Our approach will not only improve the energy harvesting efficiency, but also lower the cost by using single junction cells instead of multi-layer tandem solar cells. Moreover, this approach has the minimal disruption to the existing solar concentrator infrastructures.

Yao, Yuhan; Liu, He; Wu, Wei

2014-04-01

62

Increasing instructional efficiency by presenting additional stimuli in learning trials for children with autism spectrum disorders.  

PubMed

The current study examined the effectiveness and efficiency of presenting secondary targets within learning trials for 4 children with an autism spectrum disorder. Specifically, we compared 4 instructional conditions using a progressive prompt delay. In 3 conditions, we presented secondary targets in the antecedent or consequence portion of learning trials, or in the absence of prompts and reinforcement. In the fourth condition (control), we did not include secondary targets in learning trials. Results replicate and extend previous research by demonstrating that the majority of participants acquired secondary targets presented in the antecedent and consequent events of learning trials. PMID:24114346

Vladescu, Jason C; Kodak, Tiffany M

2013-12-01

63

Efficiency and Spectrum Enhancement in a Tapered Free-Electron Laser Amplifier  

SciTech Connect

We report the first experimental characterization of efficiency and spectrum enhancement in a laser-seeded free-electron laser using a tapered undulator. Output and spectra in the fundamental and third harmonic were measured versus distance for uniform and tapered undulators. With a 4% field taper over 3 m, a 300% (50%) increase in the fundamental (third harmonic) output was observed. A significant improvement in the spectra with the elimination of sidebands was observed using a tapered undulator. The experiment is in good agreement with predictions using the MEDUSA simulation code.

Wang, X. J.; Harder, D.; Murphy, J. B.; Qian, H.; Shen, Y.; Yang, X. [National Synchrotron Light Source, Brookhaven National Laboratory, Upton, New York 11973 (United States); Freund, H. P.; Miner, W. H. Jr. [Science Applications International Corporation, 1710 SAIC Drive, McLean, Virginia 22102 (United States)

2009-10-09

64

Effective utilization of forms for efficient office communication.  

PubMed

The efficient use of forms can increase the effectiveness of communication with the office, staff, and with the patient. An effective form meets a specific need, does so in the simplest possible way, and is flexible in its use. The use of the modified buck slip with the pegboard system directs the treatment schedule for the receptionist, gives the patient more detailed financial information, and postpones the ledger card and journal entry until a more convenient time. It also permits you to communicate with the office staff in a clear manner. At the very least it eliminates second guessing. The use of the modified truth-in-lending form increases the effectiveness of the communication with the patient as to the procedures to be performed and reinforces the diagnosis and the payment arrangements. The use of a patient treatment follow-up slip provides a simple system for communication between the postoperative patient and doctor. Such forms increase the efficiency of the total practice. PMID:267604

Lefcoe, S

1977-07-01

65

Efficient spin filter utilizing antidot potential in semiconductor heterostructures  

NASA Astrophysics Data System (ADS)

We propose a highly efficient spin filter using artificial potential created by an antidot gate-electrode, STM tip, etc., in semiconductor heterostructures in the presence of spin-orbit interaction. The strength of such a potential is electrically tunable and it can be attractive as well as repulsive. In our previous paper,footnotetextM. Eto and T. Yokoyama, J. Phys. Soc. Jpn. 78, 073710 (2009). we formulated the spin Hall effect due to the scattering by the potential in terms of phase shifts and showed that it is extremely enhanced by the resonant scattering when an attractive potential is properly tuned. In the present study, we examine three- and four-terminal devices including an artificial potential as a spin filter. We numerically evaluate the spin polarization of the output current when an unpolarized current is injected from a terminal. With an axially symmetric potential, we observe the spin polarization of more than 50%.footnotetextT. Yokoyama and M. Eto, Phys. Rev. B 80, 125311 (2009). Although the polarization is smaller when the axial symmetry is broken, we find that realistic devices could work well as an efficient spin filter.footnotetextT. Yokoyama and M. Eto, Physica E, in press.

Yokoyama, Tomohiro; Eto, Mikio

2010-03-01

66

On-board vehicular network method for efficient generator utilization  

SciTech Connect

To utilize the full power capacity of alternators the alternator phases are connected through a transformer to the rectifier which provides rectified output to a battery. The transformer has tapped windings, the taps being placed in circuit with the alternator-rectifier network in dependence on a speed control signal, for example derived from the frequency of the alternator, to effect tap changing and matching of the internal impedance of the alternator to the battery/load combination. In accordance with one feature, the taps are on the primary, and a-c switches such as triacs are selectively energized as the speed of the generator changes; in accordance with another embodiment, the taps are on the secondary of the transformer, and unilaterally conductive switches, such as thyristors or SCRs, can be used, in parallel with the rectifier diodes of the rectifying array, and selectively fired as a function of speed. A nominal output alternator thus can provide secondary output currents. The closeness of matching and eventual output power depending on the voltage rating of the alternator and the number of taps on the transformer, and hence the degree of match obtainable.

Gretsch, R.

1983-12-06

67

Theoretical investigation of the spectrum and conversion efficiency of short wavelength extreme-ultraviolet light sources based on terbium plasmas  

SciTech Connect

The emission spectrum and conversion efficiency of laser-produced terbium plasmas are theoretically investigated on the basis of computational atomic data. The theoretically calculated spectrum reproduces the main peak of observed spectrum at {lambda}=6.5 nm, which originates from 4d-4f transitions of near palladiumlike ions (Tb{sup 19+}). A simple model of the isothermal expansion of terbium plasma suggests that efficient emission can be achieved by pumping the plasma with a laser pulse at an intensity of approximately one order of magnitude greater than that used with tin sources at {lambda}=13.5 nm.

Sasaki, Akira [Quantum Beam Science Directorate, Japan Atomic Energy Agency, 8-1 Umemidai, Kizugawa-shi, Kyoto 619-0215 (Japan); Nishihara, Katsunobu [Institute of Laser Engineering, Osaka University, 2-6 Yamadaoka, Suita, Osaka 565-0871 (Japan); Sunahara, Atsushi; Furukawa, Hiroyuki [Institute for Laser Technology, 1-8-4 Utsubohonmachi, Nishi-ku, Osaka 550-0004 (Japan); Nishikawa, Takeshi [Department of Electrical and Electronic Engineering, Okayama University, 1-1 Naka 3-Chome, Tsushima, Okayama 700-8530 (Japan); Koike, Fumihiro [Physics Laboratory, School of Medicine, Kitasato University, 1-15-1 Kitasato, Sagamihara, Kanagawa 228-8555 (Japan)

2010-12-06

68

Energy-efficient new homes programs: An analysis of utility experience  

Microsoft Academic Search

This paper describes the results of a survey of thirty utilities outside the Pacific Northwest that have had practical experience in efforts to increase the efficiency of new homes built in their service areas. The experience of these utilities is examined from the standpoint of why they adopted new energy efficienct homes programs; how they structured and have implemented their

J. W. Callaway; K. W. Branch; L. J. Davis

1987-01-01

69

Sialyltransferases of marine bacteria efficiently utilize glycosphingolipid substrates.  

PubMed

Bacterial sialyltransferases (STs) from marine sources were characterized using glycosphingolipids (GSLs). Bacterial STs were found to be beta-galacotoside STs. There were two types of STs: (1) ST obtained from strains such as ishi-224, 05JTC1 (#1), ishi-467, 05JTD2 (#2), and faj-16, 05JTE1 (#3), which form alpha2-3 sialic acid (Sia) linkages, named alpha2-3ST, (2) ST obtained from strains such as ISH-224, N1C0 (#4), pda-rec, 05JTB2 (#5), and pda-0160, 05JTA2 (#6), which form alpha2-6 Sia linkages, named alpha2-6ST. All STs showed affinity to neolacto- and lacto-series GSLs, particularly in neolactotetraosyl ceramide (nLc(4)Cer). No large differences were observed in the pH and temperature profiles of enzyme activities. Kinetic parameters obtained by Lineweaver-Burk plot analysis showed that #3 and #4 STs had practical synthetic activity and thus it became easily possible to achieve large-scale ganglioside synthesis (100-300 muM) using these recombinant enzymes. Gangliosides synthesized from nLc(4)Cer by alpha2-3 and alpha2-6STs were structurally characterized by several analytical and immunological methods, and they were identified as IV(3)alphaNeuAc-nLc(4)Cer(S2-3PG) and IV(6)alphaNeuAc-nLc(4)Cer (S2-6PG), respectively. Further characterization of these STs using lactotetraosylceramide (Lc(4)Cer), neolactohexaosylceramide (i antigen), and IV(6)kladoLc(8)Cer (I antigen) showed the synthesis of corresponding gangliosides as well. Synthesized gangliosides showed binding activity to the influenza A virus [A/panama/2007/99 (H3N2)] at a similar level to purified S2-3PG and S2-6PG from mammalian sources. The above evidence suggests that these STs have unique features, including substrate specificities restricted to lacto- and neolactoseries GSLs, as well as catalytic potentials for ganglioside synthesis. This demonstrates that efficient in vitro ganglioside synthesis could be a valuable tool for selectively synthesizing Sias modifications, thereby permitting the exploration of unknown functions. PMID:19837852

Kushi, Yasunori; Kamimiya, Hisashi; Hiratsuka, Hiroko; Nozaki, Hirofumi; Fukui, Hiroshi; Yanagida, Mayumi; Hashimoto, Makoto; Nakamura, Kimihide; Watarai, Shinobu; Kasama, Takeshi; Kajiwara, Hitomi; Yamamoto, Takeshi

2010-02-01

70

On the efficiency of the Ultra Steep Spectrum technique in finding high- z radiogalaxies  

NASA Astrophysics Data System (ADS)

In the last three decades, the Ultra Steep Spectrum technique has been exploited by many groups since it was demonstrated that radio sources with very steep spectra ( ?<-1.0; S ? ? ?) are good tracers of high- z radio galaxies (HzRGs; z>2). Though more than 150 HzRGs have been discovered up to now with this technique, little is known about its real effectiveness, as most of the ongoing searches still have incomplete follow-up programs. By selecting a new appropriate sample of USS sources from the MRC survey, the true searching efficiency of the USS technique has been quantitatively demonstrated for the first time in this paper. Moreover, it was compared with that of an optical search of HzRGs based on a simple cut of the galaxies r-band magnitude distribution. When no bias other than the radio-spectrum steepness is applied, the USS technique may be up to four times more efficient in selecting HzRGs with respect to an optical search. Nevertheless, when the search is limited to objects fainter than the POSS-II plates ( r˜21), the USS technique is still 2.5 times more efficient ( ?USS=0.52 vs. ?OPT=0.19). For an optical search to reach a comparable efficiency it is necessary to select objects fainter than r=23, but this implies that about half of the HzRGs are lost because of the imposed magnitude bias. The advantage of the USS technique is that a ˜0.5 search efficiency is already reached at the POSS-II plates limit, where all the optical identification work is done without telescopes. However, this technique has the drawback that up to 40% of the HzRGs of the sample are lost simply because of the applied spectral index bias. Interestingly, the introduction of a strong angular-size bias such as ?<15? can double the searching efficiency irrespectively of the adopted technique, but only in the case that no optical bias has been introduced first.

Pedani, M.

2003-11-01

71

Spectrum Management: FCC's Licensing Approach in the 11, 18, and 23 Gigahertz Bands Currently Supports Spectrum Availability and Efficiency.  

National Technical Information Service (NTIS)

Radio-frequency spectrum is a natural resource that is used to provide an array of wireless communications services critical to the U.S. economy and a variety of government functions, such as scientific research, national defense, homeland security, and o...

2012-01-01

72

Assessment of global functioning in adolescents with autism spectrum disorders: utility of the Developmental Disability-Child Global Assessment Scale.  

PubMed

Assessment of global functioning is an important consideration in treatment outcome research; yet, there is little guidance on its evidence-based assessment for children with autism spectrum disorders. This study investigated the utility and validity of clinician-rated global functioning using the Developmental Disability-Child Global Assessment Scale in a sample of higher functioning adolescents with autism spectrum disorders and comorbid anxiety disorders enrolled in a randomized controlled trial (n = 30). Pretreatment Developmental Disability-Child Global Assessment Scale scores correlated with severity of autism spectrum disorders core symptoms (r = -.388, p = .034), pragmatic communication (r = .407, p = .032), and verbal ability (r = .449, p = .013) and did not correlate with severity of anxiety symptoms or with parent-reported adaptive behavior. Change in Developmental Disability-Child Global Assessment Scale scores during treatment was associated with autism spectrum disorders symptomatic improvement (r = .414, p = .040) and with improved general communication (r = .499, p = .013). Results support the importance of assessing global functioning in addition to symptom change and treatment response in clinical trials. PMID:23965288

White, Susan W; Smith, Laura A; Schry, Amie R

2014-05-01

73

Land Mobile Spectrum Utilization, Chicago, Illinois - Categorization of Long-Term Data.  

National Technical Information Service (NTIS)

The report characterizes the extent of radio frequency utilization by Federal Communication Commission (FCC) licensees in the Private Land Mobile Radio Services in the Chicago metropolitan area. Radio users in these services include among others: police a...

L. D. Reed K. A. Larson W. V. Tranavitch

1977-01-01

74

Efficiency of lexical access in children with autism spectrum disorders: does modality matter?  

PubMed

The provision of visual support to individuals with an autism spectrum disorder (ASD) is widely recommended. We explored one mechanism underlying the use of visual supports: efficiency of language processing. Two groups of children, one with and one without an ASD, participated. The groups had comparable oral and written language skills and nonverbal cognitive abilities. In two semantic priming experiments, prime modality and prime-target relatedness were manipulated. Response time and accuracy of lexical decisions on the spoken word targets were measured. In the first uni-modal experiment, both groups demonstrated significant priming effects. In the second experiment which was cross-modal, no effect for relatedness or group was found. This result is considered in the light of the attentional capacity required for access to the lexicon via written stimuli within the developing semantic system. These preliminary findings are also considered with respect to the use of visual support for children with ASD. PMID:24519698

Harper-Hill, Keely; Copland, David; Arnott, Wendy

2014-08-01

75

Design optimization of highly efficient spectrum-splitting and beam-concentrating diffractive optical element for lateral multijunction solar cells  

NASA Astrophysics Data System (ADS)

Two improved algorithms are proposed to extend a diffractive optical element (DOE) to work under the broad spectrum of sunlight. An optimum design has been found for the DOE, with a weighted average optical efficiency of about 6.8% better than that of the previous design. The optimization of designing high optical efficiency DOEs will pave the way for future designs of high-efficiency, low-cost lateral multijunction solar cells based on such a DOE.

Wang, Jin-Ze; Ye, Jia-Sheng; Huang, Qing-Li; Xu, Xin; Li, Dong-Mei; Meng, Qing-Bo; Yang, Guo-Zhen

2014-04-01

76

A Comparison of Health Care Utilization and Costs of Children with and without Autism Spectrum Disorders in a Large Group-Model Health Plan  

ERIC Educational Resources Information Center

Objective: Data on the current costs of medical services for children with autism spectrum disorders are lacking. Our purpose for this study was to compare health care utilization and costs of children with and without autism spectrum disorders in the same health plan. Patients and Methods: Participants included all 2- to 18-year-old children with…

Croen, Lisa A.; Najjar, Daniel V.; Ray, G. Thomas; Lotspeich, Linda; Bernal, Pilar

2007-01-01

77

Frequency-hopped spread-spectrum transmission with band-efficient modulations and simplified noncoherent sequence estimation  

Microsoft Academic Search

Frequency-hopped spread-spectrum transmission using band-efficient modulations that are phase-continuous during each hop is presented. System parameters considered include signal spectrum, reception, system complexity, and performance in noise and jamming. The particular cases where the hopped modulation is MSK, duobinary MSK, or tamed-FM are studied in detail. Results are presented for various modulation indices, rectangular and raised cosine pulse shapings, and

Yiu Ming Lam; Paul H. Wittke

1990-01-01

78

Frequency-hopped spread-spectrum transmission with band-efficient modulations and simplified noncoherent sequence estimation  

Microsoft Academic Search

Frequency-hopped spread-spectrum transmission using band-efficient modulations that are phase-continuous during each hop, is presented. A range of system parameters is considered, including signaling spectrum, reception, system complexity, and performance in the presence of noise and jamming. The particular cases where the hopped modulation is minimum-shift-keying (MSK), duobinary minimum-shift-keying (DMSK), or tamed-FM (TFM), are studied in detail. Results are presented for

Y. M. Lam; P. H. Wittke

1990-01-01

79

The utility of patient specific induced pluripotent stem cells for the modelling of Autistic Spectrum Disorders.  

PubMed

Until now, models of psychiatric diseases have typically been animal models. Whether they were to be used to further understand the pathophysiology of the disorder, or as drug discovery tools, animal models have been the choice of preference in mimicking psychiatric disorders in an experimental setting. While there have been cellular models, they have generally been lacking in validity. This situation is changing with the advent of patient-specific induced pluripotent stem cells (iPSCs). In this article, we give a methodological evaluation of the current state of the iPS technology with reference to our own work in generating patient-specific iPSCs for the study of autistic spectrum disorder (ASD). In addition, we will give a broader perspective on the validity of this technology and to what extent it can be expected to complement animal models of ASD in the coming years. PMID:23839283

Cocks, Graham; Curran, Sarah; Gami, Priya; Uwanogho, Dafe; Jeffries, Aaron R; Kathuria, Annie; Lucchesi, Walter; Wood, Victoria; Dixon, Rosemary; Ogilvie, Caroline; Steckler, Thomas; Price, Jack

2014-03-01

80

On the Achievable Efficiency-Fairness Tradeoff in Utility-Optimal MAC Protocols  

NASA Astrophysics Data System (ADS)

We use the network utility maximization (NUM) framework to create an efficient and fair medium access control (MAC) protocol for wireless networks. By adjusting the parameters in the utility objective functions of NUM problems, we control the tradeoff between efficiency and fairness of radio resource allocation through a rigorous and systematic design. In this paper, we propose a scheduling-based MAC protocol. Since it provides an upper-bound on the achievable performance, it establishes the optimality benchmarks for comparison with other algorithms in related work.

Lee, Jang-Won; Chiang, Mung; Calderbank, A. Robert

81

Design techniques for modular integrated utility systems. [energy production and conversion efficiency  

NASA Technical Reports Server (NTRS)

Features basic to the integrated utility system, such as solid waste incineration, heat recovery and usage, and water recycling/treatment, are compared in terms of cost, fuel conservation, and efficiency to conventional utility systems in the same mean-climatic area of Washington, D. C. The larger of the two apartment complexes selected for the test showed the more favorable results in the three areas of comparison. Restrictions concerning the sole use of currently available technology are hypothetically removed to consider the introduction and possible advantages of certain advanced techniques in an integrated utility system; recommendations are made and costs are estimated for each type of system.

Wolfer, B. M.

1977-01-01

82

An Approach to Integrated Spectrum Efficient Network Enhanced Telemetry (iSENET))  

NASA Technical Reports Server (NTRS)

As the integrated Network Enhanced Telemetry (iNET) program moves forward in resolving systems engineering design and architecture definition, critical technology "gaps" and a migration path to realizing the integration of this technology are needed to insure a smooth transition from the current legacy point to point telemetry links to a network oriented telemetry system. Specifically, identified by the DoD aeronautical telemetry community is the need for a migration to a network solution for command, control, and transfer of test data by optimizing the physical, data link, and network layers. In this paper, we present a network-centric telemetry approach based on variants of 802.11 that leverages the open standards as well as the previous Advanced Range Telemetry (ARTM) work on the physical layer waveform. Specifically, we present a burst modem approach based on the recent AOFDM 802.11a work, a TDMA-like MAC layer approach based on 802.11e, and then add additional MAC layer features to allow for the multi-hop aeronautical environment using a variant of the current working standards of 802.11s. The combined benefits of the variants obtained from 802.11a, 802.11e, and 802.11s address the needs for both spectrum efficiency in the aeronautical environment and the iNET program.

Okino, Clayton; Gao, Jay; Clare, Loren; Darden, Scott; Walsh, William; Loh, Kok-kiong

2006-01-01

83

Evaluation of energy efficiency of various biogas production and utilization pathways  

Microsoft Academic Search

The energy efficiency of different biogas systems, including single and co-digestion of multiple feedstock, different biogas utilization pathways, and waste-stream management strategies was evaluated. The input data were derived from assessment of existing biogas systems, present knowledge on anaerobic digestion process management and technologies for biogas system operating conditions in Germany. The energy balance was evaluated as Primary Energy Input

Martina Pöschl; Shane Ward; Philip Owende

2010-01-01

84

Efficiency enhancement utilizing hybrid charge generation layer in tandem organic light-emitting diodes  

NASA Astrophysics Data System (ADS)

We report the incorporation of lithium fluoride doped 4,7-diphenyl-1,10-phenanthroline, Al, and molybdenum trioxide which is utilized to form the charge generation layer in tandem organic light-emitting diodes. Both the fluorescent and phosphorescent tandem devices based on this hybrid charge generation layer show the enhanced luminous efficiency and reduced operating voltage compared with the devices using conventional charge generation layer. The mechanism of the efficiency enhancement is ascribed to the improvement of charge balance due to the efficient charge separation in the hybrid charge generation layer. The hybrid layer can act as the effective charge injection buffer layer as well.

Xiao, J.; Wang, X. X.; Zhu, H.; Gao, X.; Yang, Z. H.; Zhang, X. H.; Wang, S. D.

2012-07-01

85

Price-Based Spectrum Management in Cognitive Radio Networks  

Microsoft Academic Search

Cognitive radios (CRs) have a great potential to improve spectrum utilization by enabling users to access the spectrum dynamically without disturbing licensed primary radios (PRs). A key challenge in operating these radios as a network is how to implement an efficient medium access control (MAC) mechanism that can adaptively and efficiently allocate transmission powers and spectrum among CRs according to

Fan Wang; Marwan Krunz; Shuguang Cui

2008-01-01

86

Effects of space flight, clinorotation, and centrifugation on the substrate utilization efficiency of E. coli  

NASA Technical Reports Server (NTRS)

Cultures of Escherichia coli grown in space reached a 25% higher average final cell population than those in comparably matched ground controls (p<0.05). However, both groups consumed the same quantity of glucose, which suggests that space flight not only stimulated bacterial growth as has been previously reported, but also resulted in a 25% more efficient utilization of the available nutrients. Supporting experiments performed in "simulated weightlessness" under clinorotation produced similar trends of increased growth and efficiency, but to a lesser extent in absolute values. These experiments resulted in increases of 12% and 9% in average final cell population (p<0.05), while the efficiency of substrate utilization improved by 6% and 9% relative to static controls (p=0.12 and p<0.05, respectively). In contrast, hypergravity, produced by centrifugation, predictably resulted in the opposite effect--a decrease of 33% to 40% in final cell numbers with corresponding 29% to 40% lower net growth efficiencies (p<0.01). Collectively, these findings support the hypothesis that the increased bacterial growth observed in weightlessness is a result of reduced extracellular mass transport that occurs in the absence of sedimentation and buoyancy-driven convection, which consequently also improves substrate utilization efficiency in suspended cultures.

Brown, Robert B.; Klaus, D.; Todd, P.

2002-01-01

87

Efficient single-mode photon-coupling device utilizing a nanofiber tip.  

PubMed

Single-photon sources are important elements in quantum optics and quantum information science. It is crucial that such sources be able to couple photons emitted from a single quantum emitter to a single propagating mode, preferably to the guided mode of a single-mode optical fiber, with high efficiency. Various photonic devices have been successfully demonstrated to efficiently couple photons from an emitter to a single mode of a cavity or a waveguide. However, efficient coupling of these devices to optical fibers is sometimes challenging. Here we show that up to 38% of photons from an emitter can be directly coupled to a single-mode optical fiber by utilizing the flat tip of a silica nanofiber. With the aid of a metallic mirror, the efficiency can be increased to 76%. The use of a silicon waveguide further increases the efficiency to 87%. This simple device can be applied to various quantum emitters. PMID:24759303

Chonan, Sho; Kato, Shinya; Aoki, Takao

2014-01-01

88

Efficient Single-Mode Photon-Coupling Device Utilizing a Nanofiber Tip  

NASA Astrophysics Data System (ADS)

Single-photon sources are important elements in quantum optics and quantum information science. It is crucial that such sources be able to couple photons emitted from a single quantum emitter to a single propagating mode, preferably to the guided mode of a single-mode optical fiber, with high efficiency. Various photonic devices have been successfully demonstrated to efficiently couple photons from an emitter to a single mode of a cavity or a waveguide. However, efficient coupling of these devices to optical fibers is sometimes challenging. Here we show that up to 38% of photons from an emitter can be directly coupled to a single-mode optical fiber by utilizing the flat tip of a silica nanofiber. With the aid of a metallic mirror, the efficiency can be increased to 76%. The use of a silicon waveguide further increases the efficiency to 87%. This simple device can be applied to various quantum emitters.

Chonan, Sho; Kato, Shinya; Aoki, Takao

2014-04-01

89

Protein requirements of bobwhite chicks for survival, growth and efficiency of feed utilization  

USGS Publications Warehouse

During the summer and fall of 1939 four experiments were conducted at the Patuxent Research Refuge, Bowie, Maryland, to determine the protein requirements of bobwhite chicks. A total of 816 chicks were used to compare six levels of protein, namely, 22,24,26, 28, 30, and 32 per cent.....From the three standpoints of survival, rate of growth, and efficiency of feed utilization for the first ten weeks of life, the 28 per cent level of protein gave the best results. During the ninth and tenth weeks, the highest efficiency of feed utilization was obtained on the 22 per cent level. The results indicate that after the birds have reached about twothirds of their mature weight, the difference in efficiency between a diet containing 28 per cent of protein and one containing 22 per cent may be small enough to justify, in the interest of economy, the use of a diet containing the lower percentage of protein.

Nestler, R.B.; Bailey, W.W.; McClure, H.E.

1942-01-01

90

Potential utility of full-spectrum antioxidant therapy, citrulline, and dietary nitrate in the management of sickle cell disease.  

PubMed

There is considerable evidence that oxidative stress and a loss of nitric oxide bioactivity are key mediators of the vasculopathies associated with sickle cell disease. A comprehensive nutraceutical strategy for mitigating the contribution of oxidative stress to pathogenesis - dubbed "full-spectrum antioxidant therapy" - may have utility in this syndrome. This strategy entails concurrent administration of phycocyanobilin - a phytochemical richly supplied by spirulina, shown to inhibit NADPH oxidase in a manner analogous to its chemical relatives biliverdin and bilirubin; high-dose folate - recently shown to quench peroxynitrite-derived radicals and restore coupling of NO synthase; N-acetylcysteine - for boosting intracellular glutathione levels; and a phase 2 inducer such as lipoic acid - to further promote glutathione synthesis while increasing expression of antioxidant enzymes. Suboptimal endothelial arginine levels, reflecting increased plasma arginase activity and elevated ADMA, contribute to the loss of NO bioactivity in sickle cell disease; supplementation with the arginine precursor citrulline may ameliorate this defect. Increased intakes of plant-derived nitrate have the potential to diminish the quenching of NO by plasma hemoglobin in sickle cell patients, while boosting systemic NO production independent of NO synthase activity. In addition to the well-documented utility of hydroxyurea - possibly a suboptimal strategy for life-long therapy owing to its mutagenic activity - rational pharmaceutical options for managing sickle cell disease include pentoxifylline and phosphodiesterase 5 inhibitors such as sildenafil. PMID:20089363

McCarty, Mark F

2010-06-01

91

A narrowband approach to efficient PCS spectrum sharing through decentralized DCA access policies  

Microsoft Academic Search

This article addresses spectrum sharing and open access for personal communications services (PCS). Traditional regulation has allocated electromagnetic spectrum through fragmentation into mutually exclusive frequency blocks. Block allocation schemes produce trunking inefficiencies in the use of multiple narrowband RF channels. Broadband allocation schemes such as code division multiple access (CDMA) can accommodate multiple users on a single RF channel. Due

H. Salgado-Galicia; M. Sirbu; J. M. Peha

1997-01-01

92

A scoping study on energy-efficiency market transformation by California Utility DSM Programs  

SciTech Connect

Market transformation has emerged as a central policy objective for future publicly-funded energy-efficiency programs in California. California Public Utilities Commission (CPUC) Decision 95-12-063 calls for public funding to shift to activities designed to transform the energy-efficiency market. The CPUC envisions that funding {open_quotes}would only be needed for specific and limited periods of time to cause the market to be transformed{close_quotes}. At the same time, the CPUC also acknowledges that {open_quotes}there are many definitions of market transformation{close_quotes} ... and does {open_quotes}not attempt to refine those definitions today{close_quotes}. We argue that a definition of market transformation is essential. The literature is now replete with definitions, and an operational definition is needed for the CPUC to decide on which programs should be supported with public funds. The CPUC decision initially indicated a preference for programs that do not provide financial assistance 4-efficiency programs that rely on financial assistance to customers. However, energy customers have traditionally accounted for a substantial portion of California utility`s DSM programs, so the CPUC`s direction to use ratepayer funds to support programs that will transform the market raises critical questions about how to analyze what has happened in order to plan effectively for the future: Which utility energy-efficiency programs, including those that provide financial assistance to customers, have had market transforming effects? To what extent do current regulatory rules and practices encourage or discourage utilities from running programs that are designed to transform the market? Should the rules and programs be modified, and, if so, how, to promote market transformation?

Eto, J.; Prahl, R.; Schlegel, J.

1996-07-01

93

Efficient Utilization of Crude Glycerol as Fermentation Substrate in the Synthesis of Poly(3-hydroxybutyrate) Biopolymers  

Microsoft Academic Search

One refined and two crude glycerol (from biodiesel production) samples were utilized to produce poly(3-hydroxybutyrate) (PHB)\\u000a by Pseudomonas oleovorans NRRL B-14682. A batch culture fermentation protocol including 1% glycerol and an aeration rate of 3 standard liters per minute\\u000a proved best for PHB synthesis (av. yield = 1.0 ± 0.2 g\\/L at 48 h) and efficient glycerol utilization. PHB molecular weights\\u000a decreased as MeOH concentration increased.

Richard D. AshbyDaniel; Daniel K. Y. Solaiman; Gary D. Strahan

2011-01-01

94

Decision factors affecting transmission and distribution efficiency improvements by Northwest electric utilities  

SciTech Connect

The principal objective of this report was to assess and document the attitude of Northwest electric utilities toward possible BPA conservation acquisition programs that may provide incentive(s) to reduce losses on T and D lines. Secondary objectives were to examine existing incentives for making such improvements, to categorize prior T and D efficiency improvements, and to examine factors affecting the decision-making process for system improvements. Much of the information presented in the report is derived from a survey administered during personal interviews at 29 Northwest electric utilities between November 1984 and January 1985.

Hendrickson, P.L.; Darwin, R.F.

1986-01-01

95

Efficiency of utilization of nitrogen coated with urease inhibitor in maize.  

PubMed

This study aimed to evaluate under field conditions the efficiency in the use ofN coated with urease inhibitor in maize. The experiment was conducted in the year of 2007/2008. The experimental design was a randomized block design in a factorial 2 x 6, with five repetitions, constituted the N sources (common and coated with urease inhibitor) and levels (0, 40, 80, 120, 160 and 200 kg ha-1 of N) sidedressing nitrogen application in the growth stage V4. Based on the data obtained were determined recovery efficiencies, utilization, agronomic and physiological N applied. In all cases, the efficiency levels for maize were influenced by levels of sidedressing nitrogen application, in which increasing levels of N resulted in a decrease of the efficiencies, regardless of the source being common urea or coated with urease inhibitor. PMID:24498841

Okumura, Ricardo S; Mariano, Daiane de C; Zaccheo, Paulo V C; de Albuquerque, Amanda N; Giebelmeier, Carmo G; da S Lobato, Allan K; Franco, Antônio A N; de Oliveira, Neto Cândido F; Saldanha, Eduardo C M; da Conceição, Heráclito E O; da Silva, Raimundo T L

2013-09-01

96

Enhancement of separation efficiency on continuous magnetophoresis by utilizing L\\/T-shaped microchannels  

Microsoft Academic Search

In this article a novel design of on-chip continuous magnetophoretic separator was proposed by utilizing the magnetic field\\u000a and L-turning\\/T-junction effect of the flow field for high throughput applications. The motion of the magnetic bead was simulated\\u000a based on Lagrangian tracking method and the separation efficiency was calculated according to the trajectories. Impact parameters\\u000a including geometrical configuration, fluid velocity, magnetic

Xinyu Wu; Huiying Wu; Yandong Hu

2011-01-01

97

Use of radio-active phosphorus in determining the efficiency of fertilizer utilization by cacao plantation  

Microsoft Academic Search

Summary  Both P32 labelled phosphate solution and superphosphate were used in studying (1) in situ root distribution and activity of 20 year old Amelonado cacao (Theobroma Cacao L.) during wet and dry seasons and (2) the efficiency of fertilizer utilization by the cacao plantation. The P32 content of the leaves was used to determine patterns of root activity.\\u000a \\u000a Uptake of P32

Yaw Ahenkorah

1975-01-01

98

Efficient Energy Transfer in Organic Multilayer Structure Utilizing 8-Hydroxyquinoline Aluminum and Aromatic Diamine  

NASA Astrophysics Data System (ADS)

Photoluminescence from an organic multilayer structure utilizing 8-hydroxyquinoline aluminum ( Alq3) and aromatic diamine has been discussed in terms of the wavelength of the excitation light and the layer thickness. The photoluminescence intensity from Alq3 layers is enhanced in the thinner multilayer structure compared with the thicker one as a result of efficient energy transfer at the heterointerfaces. The mechanism behind the increase of photoluminescence intensity in the organic multilayer structure is discussed.

Fujii, Akihiko; Morishima, Chikayoshi; Yoshida, Masayoshi; Ohmori, Yutaka; Yoshino, Katsumi

1994-09-01

99

The politics of electric utility regulation: Explaining energy efficiency policy in the states  

NASA Astrophysics Data System (ADS)

Even with broad societal pressures to alter the regulatory environment in the states with regard to the efficient use of electricity, many states have not made what some conservation advocates believe are adequate reforms for increasing levels of energy efficiency. While some states have comprehensive policies that require electric utilities to engage in integrated resource planning and demand-side management (DSM), along with providing utilities with a regulatory framework that allows for the recovery of energy efficiency program costs and lost revenues, other states have no such policies. The main purpose of this inquiry is twofold: first, it discusses some of the current regulatory issues being explored at the state level in an attempt to determine how states vary in their development and application of energy efficiency regulations; and second, it attempts to explain why the states differ in their development of energy efficiency regulations. The application of the analytical framework developed in this study proves useful for assessing the various elements that affect state regulatory policy development. Organized interests, state political culture, and various state economic variables tend to exert considerable influence over regulatory policy choice. However, other factors such as government institutions, including state legislatures and regulatory agencies, were not without effect. Though the directions of some of the relationships were unexpected, various logistic regression models show that each of the approaches to the study of regulation is useful in explaining the process of developing and adopting innovative energy efficiency policies. In the area of electric utility regulation, and more specifically energy efficiency regulation, this analysis finds that, in general, the likelihood of a state adopting DSM-related lost revenue recovery and/or sharehoider incentives on DSM programs, as well as stringent cost-effectiveness tests, is greater for states with Republican governors, Democratic and professionalized legislatures, dominant interest groups, higher levels of GSP, greater growth in per capita personal income, traditionalistic political cultures, and lower levels of environmental commitment. Moreover, economics is not always the most influential factor in determining regulatory policy. Rather, political institutions and government bureaucracies make a considerable difference.

Altman, John Arthur

100

[Research practices of conversion efficiency of resources utilization model of castoff from Chinese material medica industrialization].  

PubMed

The industrialization chains and their products, which were formed from the process of the production of medicinal materials-prepared drug in pieces and deep processed product of Chinese material medica (CMM) resources, have generated large benefits of social and economic. However, The large of herb-medicine castoff of "non-medicinal parts" and "rejected materials" produced inevitably during the process of Chinese medicinal resources produce and process, and the residues, waste water and waste gas were produced during the manufactured and deep processed product of CMM. These lead to the waste of resources and environmental pollution. Our previous researches had proposed the "three utilization strategies" and "three types of resources models" of herb-medicine castoff according to the different physicochemical property of resources constitutes, resources potential and utility value of herb-medicine castoff. This article focus on the conversion efficiency of resources model and analysis the ways, technologies, practices, and application in herb-medicine cast off of the conversion efficiency of resources model based on the recycling economy theory of resources and thoughts of resources chemistry of CMM. These data may be promote and resolve the key problems limited the industrialization of Chinese material medica for long time and promote the realization of herb-medicine castoff resources utilization. PMID:24791476

Duan, Jin-Ao; Su, Shu-Lan; Guo, Sheng; Liu, Pei; Qian, Da-Wei; Jiang, Shu; Zhu, Hua-Xu; Tang, Yu-Ping; Wu, Qi-Nan

2013-12-01

101

Selective oxidation of arsenite by peroxymonosulfate with high utilization efficiency of oxidant.  

PubMed

Oxidation of arsenite (As(III)) is a critical yet often weak link in many current technologies for remediating contaminated groundwater. We report a novel, efficient oxidation reaction for As(III) conversion to As(V) using commercial available peroxymonosulfate (PMS). As(III) is rapidly oxidized by PMS with a utilization efficiency larger than 90%. Increasing PMS concentrations and pH accelerate oxidation of As(III), independent to the availability of dissolved oxygen. The addition of PMS enables As(III) to oxidize completely to As(V) within 24 h, even in the presence of high concentrations of radical scavengers. On the basis of these observations and theoretical calculations, a two-electron transfer (i.e., oxygen atom transfer) reaction pathway is proposed. Direct oxidation of As(III) by PMS avoids the formation of nonselective reactive radicals, thus minimizing the adverse impact of coexisting organic matter and maximizing the utilization efficiency of PMS. Therefore, this simple approach is considered a cost-effective water treatment method for the oxidation of As(III) to As(V). PMID:24580110

Wang, Zhaohui; Bush, Richard T; Sullivan, Leigh A; Chen, Chuncheng; Liu, Jianshe

2014-04-01

102

NAAPRO detector model, a versatile and efficient approach to ?-ray spectrum simulation  

Microsoft Academic Search

The paper describes a detector model which is used by the Neutron Activation Analysis PRognosis and Optimization (NAAPRO) code for modeling ?-ray spectra of the activation products generated by neutron irradiation of hypothetical multielement samples with user-specified composition. Distinctive features of the model are its sufficiently high productivity, flexibility and accuracy, which allow quickly obtaining a model ?-spectrum for a

A. N. Berlizov; V. K. Basenko; R. H. Filby; I. A. Malyuk; V. V. Tryshyn

2006-01-01

103

An aggregated perylene-based broad-spectrum, efficient and label-free quencher for multiplexed fluorescent bioassays.  

PubMed

Fluorescent sensing systems based on the quenching of fluorophores have found wide applications in bioassays. An efficient quencher will endow the sensing system a high sensitivity. The frequently used quenchers are based on organic molecules or nanomaterials, which usually need tedious synthesizing and modifying steps, and exhibit different quenching efficiencies to different fluorophores. In this work, we for the first time report that aggregated perylene derivative can serve as a broad-spectrum and label-free quencher that is able to efficiently quench a variety of fluorophores, such as green, red and far red dyes labeled on DNA. By choosing nucleases as model biomolecules, such a broad-spectrum quencher was then employed to construct a multiplexed bioassay platform through a label-free manner. Due to the high quenching efficiency of the aggregated perylene, the proposed platform could detect nuclease with high sensitivity, with a detection limit of 0.03U/mL for EcoRV, and 0.05U/mL for EcoRI. The perylene quencher does not affect the activity of nuclease, which makes it possible to design post-addition type bioassay platform. Moreover, the proposed platform allows simultaneous and multicolor analysis of nucleases in homogeneous solution, demonstrating its value of potential application in rapid screening of multiple bio-targets. PMID:24662061

Liu, Tao; Hu, Rong; Lv, Yi-Fan; Wu, Yuan; Liang, Hao; Huan, Shuang-Yan; Zhang, Xiao-Bing; Tan, Weihong; Yu, Ru-Qin

2014-08-15

104

Engineered Enterobacter aerogenes for efficient utilization of sugarcane molasses in 2,3-butanediol production.  

PubMed

Sugarcane molasses is considered to be a good carbon source for biorefinery due to its high sugar content and low price. Sucrose occupies more than half of the sugar in the molasses. Enterobacter aerogenes is a good host strain for 2,3-butanediol production, but its utilization of sucrose is not very efficient. To improve sucrose utilization in E. aerogenes, a sucrose regulator (ScrR) was disrupted from the genomic DNA. The deletion mutation increased the sucrose consumption rate significantly when sucrose or sugarcane molasses was used as a carbon source. The 2,3-butanediol production from sugarcane molasses by the mutant was enhanced by 60% in batch fermentation compared to that by the wild type strain. In fed-batch fermentation, 98.69 g/L of 2,3-butanediol production was achieved at 36 h. PMID:23644066

Jung, Moo-Young; Park, Bu-Soo; Lee, Jinwon; Oh, Min-Kyu

2013-07-01

105

Arc View/Avenue: Coding styles and utility scripts for efficient development  

SciTech Connect

Effectiveness and efficiency of software development can be greatly increased by writing modularized code using informal (styles) and formal (standards) work approaches. Software development is about connecting pieces into a coherent whole. Thus consistent work approaches provide a structure that allows individuals and teams to minimize the time and thought put into making these connections. These investments in structure return even more benefits in the maintenance phase when old code has to be examined by new programmers, or after time has passed. We present some examples of coding style for Avenue: a simplified form of Hungarian notation (notationHungarian, stringCustomerName, etc.), script naming prefixes and suffixes, and options in script headers. We demonstrate several modular, object-like utility scripts that can be used alone or combined into other utilities. These include developer tools such as a System.Echo substitute for Windows, a Window inspector, and a script for detecting and dealing with multiple display resolutions.

Ganter, J.

1996-05-07

106

Energetic efficiency of starch, protein and lipid utilization in growing pigs.  

PubMed

Mathematical models are increasingly used to predict the response of an animal to a changing nutrient supply. The objective of this experiment was to provide data that can be used in model development or evaluation and concerns the energetic efficiency with which nutrients are used for protein and lipid deposition. A basal diet (D1), limiting in lysine supply, was fed at 1.7 MJ metabolizable energy (ME)/(kg BW(0.60) x d1) to growing pigs that weighed approximately 60 kg. Four additional diets were formulated: the basal diet and a dietary supplement that consisted of starch (D2), starch and corn gluten meal (D3), starch and casein (D4) or starch and lipid (D5). The latter four diets were fed at 2.55 MJ ME/(kg BW(0.60) x d1) and ensured the same intake of the basal diet across treatments; the difference was supplied by the supplement. Metabolic utilization of the basal diet and supplements was determined using nitrogen and energy balances (indirect calorimetry). The N retention was similar in pigs fed diets D1, D2, D3 and D5 but considerably higher in those fed D4. A data analysis model was developed to account for differences in ME utilization between nutrients. The ME not deposited as protein entered a common pool of energy, which was used for adenosine triphosphate synthesis or lipid deposition. The energetic efficiencies of ME utilization were 0.842, 0.520 and 0.883 for starch, protein and lipid, respectively. Due to the energy cost of protein deposition (or protein turnover), the energetic efficiencies of depositing dietary protein as protein or lipid were similar. PMID:11285343

van Milgen, J; Noblet, J; Dubois, S

2001-04-01

107

Efficient polarized light-emitting diodes utilizing ultrathin photoaddressable alignment layers  

NASA Astrophysics Data System (ADS)

We demonstrate that an ultrathin photoaddressable polymer (PAP) layer with a thickness as small as 5 nm can be utilized for the monodomain alignment of thermotropic liquid crystalline polyfluorene. The optical anisotropies in absorption and emission are found to be independent of the PAP layer thickness within a range of 5 to 30 nm. On the other hand, decreasing the PAP layer thickness greatly improves the performance of polarized blue light-emitting diodes: With a PAP layer thickness of only 10 nm, the device turns on at 5 V and reaches a brightness of 100 cd/m2 at 8 V with an efficiency of 0.66 cd/A.

Yang, X. H.; Neher, D.; Lucht, S.; Nothofer, H.; Güntner, R.; Scherf, U.; Hagen, R.; Kostromine, S.

2002-09-01

108

Federal government, utility, manufacturer: A unique partnership for comprehensive water efficiency  

SciTech Connect

A partnership among the Federal government, a utility, and water efficient equipment manufacturers was developed in response to the Executive Order 12902, Energy and Efficiency in Federal Facilities, where water conservation is still a fairly undeveloped part of resource conservation in the Federal government. The Department of Energy`s Federal Energy Management Program (with the National Renewable Energy Laboratory) managed the project, bringing together the Environmental Protection Agency, General Services Administration and Bureau of Reclamation with Denver Water and four water use equipment manufacturers to install and test water-saving indoor and outdoor technologies at the Denver Federal Center. This paper will describe the process used to form this partnership and document the results and its potential impact.

Mayo, K.

1995-10-01

109

Metabolic and Regulatory Rearrangements Underlying Efficient d-Xylose Utilization in Engineered Pseudomonas putida S12*  

PubMed Central

Previously, an efficient d-xylose utilizing Pseudomonas putida S12 strain was obtained by introducing the d-xylose isomerase pathway from Escherichia coli, followed by evolutionary selection. In the present study, systemic changes associated with the evolved phenotype were identified by transcriptomics, enzyme activity analysis, and inverse engineering. A key element in improving the initially poor d-xylose utilization was the redistribution of 6-phospho-d-gluconate (6-PG) between the Entner-Doudoroff pathway and the oxidative pentose phosphate (PP) pathway. This redistribution increased the availability of 6-PG for oxidative decarboxylation to d-ribose-5-phosphate, which is essential for the utilization of d-xylose via the nonoxidative PP pathway. The metabolic redistribution of 6-PG was procured by modified HexR regulation, which in addition appeared to control periplasmic sugar oxidation. Because the absence of periplasmic d-xylonate formation was previously demonstrated to be essential for achieving a high biomass yield on d-xylose, the aberrant HexR control appeared to underlie both the improved growth rate and biomass yield of the evolved d-xylose utilizing P. putida strain. The increased oxidative PP pathway activity furthermore resulted in an elevated NADH/NAD+ ratio that caused the metabolic flux to be redirected from the TCA cycle to the glyoxylate shunt, which was also activated transcriptionally. Clearly, these findings may serve as an important case in point to engineer and improve the utilization of non-natural carbon sources in a wide range of industrial microorganisms.

Meijnen, Jean-Paul; de Winde, Johannes H.; Ruijssenaars, Harald J.

2012-01-01

110

NAAPRO detector model, a versatile and efficient approach to gamma-ray spectrum simulation  

Microsoft Academic Search

The paper describes a detector model which is used by the Neutron Activation Analysis PRognosis and Optimization (NAAPRO) code for modeling gamma-ray spectra of the activation products generated by neutron irradiation of hypothetical multielement samples with user-specified composition. Distinctive features of the model are its sufficiently high productivity, flexibility and accuracy, which allow quickly obtaining a model gamma-spectrum for a

A. N. Berlizov; V. K. Basenko; R. H. Filby; I. A. Malyuk; V. V. Tryshyn

2006-01-01

111

Study of the X-ray energy utilization efficiency of the X-ray digital imaging systems in industrial applications  

Microsoft Academic Search

The purpose of the present paper is to study the X-ray energy utilization efficiency that is inherent in the improved design of actual X-ray digital imaging systems in industrial applications. Both the X-ray energy utilization efficiency and the light intensity of the X-ray beam are lowered distinctly while the distance of the focal length is increased for high spatial resolution

Li Ruihong; Han Yueping

2010-01-01

112

Instantaneous Shoreline Extraction Utilizing Integrated Spectrum and Shadow Analysis From LiDAR Data and High-resolution Satellite Imagery  

NASA Astrophysics Data System (ADS)

Shoreline delineation and shoreline change detection are expensive processes in data source acquisition and manual shoreline delineation. These costs confine the frequency and interval of shoreline mapping periods. In this dissertation, a new shoreline delineation approach was developed targeting on lowering the data source cost and reducing human labor. To lower the cost of data sources, we used the public domain LiDAR data sets and satellite images to delineate shorelines without the requirement of data sets being acquired simultaneously, which is a new concept in this field. To reduce the labor cost, we made improvements in classifying LiDAR points and satellite images. Analyzing shadow relations with topography to improve the satellite image classification performance is also a brand-new concept. The extracted shoreline of the proposed approach could achieve an accuracy of 1.495 m RMSE, or 4.452m at the 95% confidence level. Consequently, the proposed approach could successfully lower the cost and shorten the processing time, in other words, to increase the shoreline mapping frequency with a reasonable accuracy. However, the extracted shoreline may not compete with the shoreline extracted by aerial photogrammetric procedures in the aspect of accuracy. Hence, this is a trade-off between cost and accuracy. This approach consists of three phases, first, a shoreline extraction procedure based mainly on LiDAR point cloud data with multispectral information from satellite images. Second, an object oriented shoreline extraction procedure to delineate shoreline solely from satellite images; in this case WorldView-2 images were used. Third, a shoreline integration procedure combining these two shorelines based on actual shoreline changes and physical terrain properties. The actual data source cost would only be from the acquisition of satellite images. On the other hand, only two processes needed human attention. First, the shoreline within harbor areas needed to be manually connected, for its length was less than 3% of the total shoreline length in our dataset. Secondly, the parameters for satellite image classification needed to be manually determined. The need for manpower was significantly less compared to the ground surveying or aerial photogrammetry. The first phase of shoreline extraction was to utilize Normalized Difference Vegetation Index (NDVI), Mean-Shift segmentation on the coordinate (X, Y, Z), and attributes (multispectral bands from satellite images) of the LiDAR points to classify each LiDAR point into land or water surface. Boundary of the land points were then traced to create the shoreline. The second phase of shoreline extraction solely from satellite images utilized spectrum, NDVI, and shadow analysis to classify the satellite images into classes. These classes were then refined by mean-shift segmentation on the panchromatic band. By tracing the boundary of the water surface, the shoreline can be created. Since these two shorelines may represent different shoreline instances in time, evaluating the changes of shoreline was the first to be done. Then an independent scenario analysis and a procedure are performed for the shoreline of each of the three conditions: in the process of erosion, in the process of accession, and remaining the same. With these three conditions, we could analysis the actual terrain type and correct the classification errors to obtain a more accurate shoreline. Meanwhile, methods of evaluating the quality of shorelines had also been discussed. The experiment showed that there were three indicators could best represent the quality of the shoreline. These indicators were: (1) shoreline accuracy, (2) land area difference between extracted shoreline and ground truth shoreline, and (3) bias factor from shoreline quality metrics.

Lee, I.-Chieh

113

A cross-layer protocol of spectrum mobility and handover in cognitive LTE networks  

Microsoft Academic Search

Cognitive radio technique is the next step toward efficient wireless bandwidth utilization. While some of the spectrum bands (unlicensed band) have been increasingly used, most of the other spectrum resources (licensed band) are underutilized. This drives the challenges of open spectrum and dynamic spectrum access concepts, which allows unlicensed users (or called secondary users, SUs) equipped with cognitive radios to

Yuh-Shyan Chen; Ching-Hsiung Cho; Ilsun You; Han-Chieh Chao

2011-01-01

114

BRIEF COMMUNICATIONS: Investigation of the gain and emission spectrum of a TE laser utilizing a mixture of isotopically substituted carbon dioxide molecules  

Microsoft Academic Search

The results are presented of theoretical and experimental investigations of the gain and emission spectrum of a TE laser utilizing a mixture of isotopically substituted 12CO2 and 13CO2 molecules. It was found that, in a wide range of active-medium pressures (p = 100-3500 Torr) and excitation levels (T3 = 1200-2400 K), a gas mixture such the concentration of 13CO2 (x13)

V. O. Petukhov; N. N. Sazhina; V. S. Starovoitov; S. A. Trushin; N. V. Cheburkin; S. K. Chekin; V. V. Churakov

1985-01-01

115

Efficient simultaneous fluorescence orientation, spectrum, and lifetime detection for single molecule dynamics  

NASA Astrophysics Data System (ADS)

We report on the simultaneous detection of the fluorescence lifetime, spectrum, and three-dimensional dipole orientation determination of single perylene diimide molecules deposited on a silica surface as a model system for studying fluorophore internal and orientational dynamics. We employ a multi-parameter detection scheme to demonstrate how jumps in the orientation of the molecule can be disentangled from spectral jumps, both leading to changes of the detected total fluorescence intensity. The fluorescence lifetime determined simultaneously from the same photons is also sensitive to the orientation of the dipole with respect to the interface between media with different refractive indices. The correlated changes of the lifetime and orientation we observe are in good agreement with theory.

Börner, Richard; Kowerko, Danny; Krause, Stefan; Borczyskowski, Christian von; Hübner, Christian G.

2012-10-01

116

The effect of physician practice organization on efficient utilization of hospital resources.  

PubMed Central

OBJECTIVE. This study examines variations in the efficient use of hospital resources across individual physicians. DATA SOURCES AND SETTING. The study is conducted over a two-year period (1989-1990) in all short-term general hospitals with 50 or more beds in Arizona. We examine hospital discharge data for 43,625 women undergoing cesarean sections and vaginal deliveries without complications. These data include physician identifiers that permit us to link patient information with information on physicians provided by the state medical association. STUDY DESIGN. The study first measures the contribution of physician characteristics to the explanatory power of regression models that predict resource use. It then tests hypothesized effects on resource utilization exerted by two sets of physician level factors: physician background and physician practice organization. The latter includes effects of hospital practice volume, concentration of hospital practice, percent managed care patients in one's hospital practice, and diversity of patients treated. Efficiency (inefficiency) is measured as the degree of variation in patient charges and length of stay below (above) the average of treating all patients with the same condition in the same hospital in the same year with the same severity of illness, controlling for discharge status and the presence of complications. PRINCIPAL FINDINGS. After controlling for patient factors, physician characteristics explain a significant amount of the variability in hospital charges and length of stay in the two maternity conditions. Results also support hypotheses that efficiency is influenced by practice organization factors such as patient volume and managed care load. Physicians with larger practices and a higher share of managed care patients appear to be more efficient. CONCLUSIONS. The results suggest that health care reform efforts to develop physician-hospital networks and managed competition may promote greater parsimony in physicians' practice behavior.

Burns, L R; Chilingerian, J A; Wholey, D R

1994-01-01

117

Copper catalysis for enhancement of cobalt leaching and acid utilization efficiency in microbial fuel cells.  

PubMed

Enhancement of both cobalt leaching from LiCoO2 and acid utilization efficiency (AUE) in microbial fuel cells (MFCs) was successfully achieved by the addition of Cu(II). A dosage of 10mg/L Cu(II) improved both cobalt leaching up to 308% and AUE of 171% compared to the controls with no presence of Cu(II). The apparent activation energy of cobalt leaching catalyzed by Cu(II) in MFCs was only 11.8 kJ/mol. These results demonstrate cobalt leaching in MFCs using Cu(II) as a catalyst may be an effective strategy for cobalt recovery and recycle of spent Li-ion batteries, and the evidence of influence factors including solid/liquid ratio, temperature, and pH and solution conductivity can contribute to improving understanding of and optimizing cobalt leaching catalyzed by Cu(II) in MFCs. PMID:24007993

Liu, Yaxuan; Shen, Jingya; Huang, Liping; Wu, Dan

2013-11-15

118

Spectral Efficiency of FM and ACSB Radios.  

National Technical Information Service (NTIS)

In this second of nine reports concerning spectrum efficient technologies, the spectral efficiency of amplitude compandored single sideband (ACSB) radios is compared with that of conventional frequency modulation (FM) radios utilizing five kilohertz frequ...

M. Herro

1980-01-01

119

On-Site Fabrication Infrastructure to Enable Efficient Exploration and Utilization of Space  

NASA Technical Reports Server (NTRS)

Unlike past one-at-a-time mission approaches, system-of-systems infrastructures will be needed to enable ambitious scenarios for sustainable future space exploration and utilization. So what do we do when we get to the moon for sustainable exploration. On-site fabrication infrastructure will be needed to support habitat structure development, tools and mechanical part fabrication, as well as repair and replacement of ground support and space mission hardware such as life support items, vehicle components and crew systems. The on-site fabrication infrastructure will need the In Situ Fabrication and Repair (ISFR) element, which is working in conjunction with the In Situ Resources Utilization (ISRU) element, to live off the land. The ISFR element has worked closely with the ISRU element in the past year to assess the ability of using lunar regolith as a viable feedstock for fabrication material. Preliminary work has shown promise and the ISFR Element will continue to concentrate on this activity. Fabrication capabilities have been furthered with the process certification effort that, when completed, will allow for space-qualified hardware to be manufactured. Materials being investigated include titanium and aluminum alloys as well as lunar regolith simulants with binders. This paper addresses the latest advancements made in the fabrication of infrastructures that support efficient, affordable, reliable infrastructures for both space exploration systems and logistics; infrastructures that allow sustained, affordable and highly effective operations on the Moon and beyond.

Howell, Joe T.; Fikes, John C.; McLemore, Carole A.; Good, James E.

2008-01-01

120

Efficient, full-spectrum, long-lived, non-toxic microwave lamp for plant growth  

NASA Technical Reports Server (NTRS)

Fusion Systems Corporation has developed a mercury-free, low infrared, efficient microwave lamp using a benign sulfur based fill optimized for visible light. Our literature search and discussions with researchers directed us to enhance the bulbs red output. We have demonstrated a photosynthetic efficacy of over 2 micro-moles per microwave joule which corresponds to over 1.3 micro-moles per joule at the power main. Recent work has shown we can make additional increases in overall system efficiency. During the next two years, we expect to demonstrate a system capable of producing more than 1.5 micro-moles/joule measured at the power main with significantly less IR than alternative lamp systems. We determined optimal plant growth light requirements via a literature search and researcher input. We surveyed candidate lamp fill materials to be used in combination with sulfur and explored several methods of increasing photosynthetic efficacy.

Maclennan, Donald A.; Turner, Brian P.; Dolan, James T.; Ury, Michael G.; Gustafson, Paul

1994-01-01

121

Spectrum efficiency improvement of directly detected OFDM based on balance receiver  

NASA Astrophysics Data System (ADS)

A novel optical single-sideband directly detected orthogonal frequency division multiplexing (DD-OFDM) system based on balance receiver consisting of two PINs is proposed and demonstrated. By introducing phase shift of ? to one arm of the proposed receiver, inter-modulation distortion (IMD) near the optical carrier can be eliminated efficiently. The simulation results show that our system improves spectral efficiency to about 1.54 bps/Hz with 4-quadrature amplitude modulation (4QAM) mapping, and the optical carrier and signal power ratio (CSPR) has negligible impact on the OSNR performance, which can be improved by 3 dB with negligible error vector magnitude (EVM) penalty. Additionally, the optimum CSPR can be controlled by adjusting them respectively. 5 Gbit/s data with 4QAM mapping and 6.25% cyclic prefix (CP) inserted is successfully transmitted over 320 km of standard single mode fiber (SSMF) and our system exhibits a negligible penalty. Higher spectral efficiency can be achieved with more complex modulation formats and polarization multiplexing.

Tang, Chao; Chen, Hongwei; Chen, Minghua; Xie, Shizhong

2009-11-01

122

Overcoming barriers to the clinical utilization of iPSCs: reprogramming efficiency, safety and quality.  

PubMed

Differentiated cells can be reprogrammed into pluripotent stem cells, known as "induced pluripotent stem cells" (iPSCs), through the overexpression of defined transcription factors. The creation of iPSC lines has opened new avenues for patient-specific cell replacement therapies for regenerative medicine. However, the clinical utilization of iPSCs is largely impeded by two limitations. The first limitation is the low efficiency of iPSCs generation from differentiated cells. The second limitation is that many iPSC lines are not authentically pluripotent, as many cell lines inefficiently differentiate into differentiated cell types when they are tested for their ability to complement embryonic development. Thus, the "quality" of iPSCs must be increased if they are to be differentiated into specialized cell types for cell replacement therapies. Overcoming these two limitations is paramount to facilitate the widespread employment of iPSCs for therapeutic purposes. Here, we summarize recent progress made in strategies enabling the efficient production of high-quality iPSCs, including choice of reprogramming factors, choice of target cell type, and strategies to improve iPSC quality. PMID:23073833

Cao, Suying; Loh, Kyle; Pei, Yangli; Zhang, Wei; Han, Jianyong

2012-11-01

123

Exploring the Utility of Narrative Analysis in Diagnostic Decision Making: Picture-Bound Reference, Elaboration, and Fetal Alcohol Spectrum Disorders  

ERIC Educational Resources Information Center

Purpose: To evaluate classification accuracy and clinical feasibility of a narrative analysis tool for identifying children with a fetal alcohol spectrum disorder (FASD). Method: Picture-elicited narratives generated by 16 age-matched pairs of school-aged children (FASD vs. typical development [TD]) were coded for semantic elaboration and…

Thorne, John C.; Coggins, Truman E.; Olson, Heather Carmichael; Astley, Susan J.

2007-01-01

124

EASY-GOING deconvolution: Automated MQMAS NMR spectrum analysis based on a model with analytical crystallite excitation efficiencies  

NASA Astrophysics Data System (ADS)

The EASY-GOING deconvolution (EGdeconv) program is extended to enable fast and automated fitting of multiple quantum magic angle spinning (MQMAS) spectra guided by evolutionary algorithms. We implemented an analytical crystallite excitation model for spectrum simulation. Currently these efficiencies are limited to two-pulse and z-filtered 3QMAS spectra of spin 3/2 and 5/2 nuclei, whereas for higher spin-quantum numbers ideal excitation is assumed. The analytical expressions are explained in full to avoid ambiguity and facilitate others to use them. The EGdeconv program can fit interaction parameter distributions. It currently includes a Gaussian distribution for the chemical shift and an (extended) Czjzek distribution for the quadrupolar interaction. We provide three case studies to illustrate EGdeconv's capabilities for fitting MQMAS spectra. The EGdeconv program is available as is on our website http://egdeconv.science.ru.nl for 64-bit Linux operating systems.

Grimminck, Dennis L. A. G.; van Meerten, Bas; Verkuijlen, Margriet H. W.; van Eck, Ernst R. H.; Leo Meerts, W.; Kentgens, Arno P. M.

2013-03-01

125

EASY-GOING deconvolution: Automated MQMAS NMR spectrum analysis based on a model with analytical crystallite excitation efficiencies.  

PubMed

The EASY-GOING deconvolution (EGdeconv) program is extended to enable fast and automated fitting of multiple quantum magic angle spinning (MQMAS) spectra guided by evolutionary algorithms. We implemented an analytical crystallite excitation model for spectrum simulation. Currently these efficiencies are limited to two-pulse and z-filtered 3QMAS spectra of spin 3/2 and 5/2 nuclei, whereas for higher spin-quantum numbers ideal excitation is assumed. The analytical expressions are explained in full to avoid ambiguity and facilitate others to use them. The EGdeconv program can fit interaction parameter distributions. It currently includes a Gaussian distribution for the chemical shift and an (extended) Czjzek distribution for the quadrupolar interaction. We provide three case studies to illustrate EGdeconv's capabilities for fitting MQMAS spectra. The EGdeconv program is available as is on our website http://egdeconv.science.ru.nl for 64-bit Linux operating systems. PMID:23376481

Grimminck, Dennis L A G; van Meerten, Bas; Verkuijlen, Margriet H W; van Eck, Ernst R H; Meerts, W Leo; Kentgens, Arno P M

2013-03-01

126

Efficient reduction of complex noise in passive millimeter-wavelength video utilizing Bayesian surprise  

NASA Astrophysics Data System (ADS)

Passive millimeter wavelength (PMMW) video holds great promise given its ability to see targets and obstacles through fog, smoke and rain. However, current imagers produce undesirable complex noise. This can come as a mixture of fast shot (snow like) noise and a slower forming circular fixed pattern. Shot noise can be removed by a simple gain style filter. However, this can produce blurring of objects in the scene. To alleviate this, we measure the amount of Bayesian surprise in videos. Bayesian surprise is feature change in time which is abrupt, but cannot be accounted for as shot noise. Surprise is used to attenuate the shot noise filter in locations of high surprise. Since high Bayesian surprise in videos is very salient to observers, this reduces blurring particularly in places where people visually attend. Fixed pattern noise is removed after the shot noise using a combination of Non-uniformity correction (NUC) and Eigen Image Wavelet Transformation. The combination allows for online removal of time varying fixed pattern noise even when background motion may be absent. It also allows for online adaptation to differing intensities of fixed pattern noise. The fixed pattern and shot noise filters are all efficient allowing for real time video processing of PMMW video. We show several examples of PMMW video with complex noise that is much cleaner as a result of the noise removal. Processed video clearly shows cars, houses, trees and utility poles at 20 frames per second.

Mundhenk, T. Nathan; Baron, Josh; Matic, Roy M.

2011-05-01

127

Establishing an Efficient Way to Utilize the Drought Resistance Germplasm Population in Wheat  

PubMed Central

Drought resistance breeding provides a hopeful way to improve yield and quality of wheat in arid and semiarid regions. Constructing core collection is an efficient way to evaluate and utilize drought-resistant germplasm resources in wheat. In the present research, 1,683 wheat varieties were divided into five germplasm groups (high resistant, HR; resistant, R; moderate resistant, MR; susceptible, S; and high susceptible, HS). The least distance stepwise sampling (LDSS) method was adopted to select core accessions. Six commonly used genetic distances (Euclidean distance, Euclid; Standardized Euclidean distance, Seuclid; Mahalanobis distance, Mahal; Manhattan distance, Manhat; Cosine distance, Cosine; and Correlation distance, Correlation) were used to assess genetic distances among accessions. Unweighted pair-group average (UPGMA) method was used to perform hierarchical cluster analysis. Coincidence rate of range (CR) and variable rate of coefficient of variation (VR) were adopted to evaluate the representativeness of the core collection. A method for selecting the ideal constructing strategy was suggested in the present research. A wheat core collection for the drought resistance breeding programs was constructed by the strategy selected in the present research. The principal component analysis showed that the genetic diversity was well preserved in that core collection.

Wang, Jiancheng; Guan, Yajing; Wang, Yang; Zhu, Liwei; Wang, Qitian; Hu, Qijuan; Hu, Jin

2013-01-01

128

Establishing an efficient way to utilize the drought resistance germplasm population in wheat.  

PubMed

Drought resistance breeding provides a hopeful way to improve yield and quality of wheat in arid and semiarid regions. Constructing core collection is an efficient way to evaluate and utilize drought-resistant germplasm resources in wheat. In the present research, 1,683 wheat varieties were divided into five germplasm groups (high resistant, HR; resistant, R; moderate resistant, MR; susceptible, S; and high susceptible, HS). The least distance stepwise sampling (LDSS) method was adopted to select core accessions. Six commonly used genetic distances (Euclidean distance, Euclid; Standardized Euclidean distance, Seuclid; Mahalanobis distance, Mahal; Manhattan distance, Manhat; Cosine distance, Cosine; and Correlation distance, Correlation) were used to assess genetic distances among accessions. Unweighted pair-group average (UPGMA) method was used to perform hierarchical cluster analysis. Coincidence rate of range (CR) and variable rate of coefficient of variation (VR) were adopted to evaluate the representativeness of the core collection. A method for selecting the ideal constructing strategy was suggested in the present research. A wheat core collection for the drought resistance breeding programs was constructed by the strategy selected in the present research. The principal component analysis showed that the genetic diversity was well preserved in that core collection. PMID:23737717

Wang, Jiancheng; Guan, Yajing; Wang, Yang; Zhu, Liwei; Wang, Qitian; Hu, Qijuan; Hu, Jin

2013-01-01

129

Utility and Performance Relative to Consumer Product Energy Efficiency Standards. Final Technical Report.  

National Technical Information Service (NTIS)

An investigation of the relative utility and performance of nine major household consumer products covered by the Energy Policy and Conservation Act is summarized. The objective was to define the terms utility and performance, to recommend methods for qua...

J. L. Coggins

1979-01-01

130

Recycling Limestone for SO2 Absorption: Pollutant-absorbing material is utilized more efficiently.  

National Technical Information Service (NTIS)

This citation summarizes a one-page announcement of technology available for utilization. Partially reacted limestone used for removing sulfur dioxide during the fluidized combustion of coal can be reactivated by hydration. This increased utilization woul...

1983-01-01

131

Genome sequence of the thermophilic strain Bacillus coagulans XZL4, an efficient pentose-utilizing producer of chemicals.  

PubMed

Bacillus coagulans XZL4 is an efficient pentose-utilizing producer of important platform compounds, such as l-lactic acid, 2,3-butanediol, and acetoin. Here we present a 2.8-Mb assembly of its genome. Simple and efficient carbohydrate metabolism systems, especially the transketolase/transaldolase pathway, make it possible to convert pentose sugars to products at high levels. PMID:22038963

Su, Fei; Xu, Ke; Zhao, Bo; Tai, Cui; Tao, Fei; Tang, Hongzhi; Xu, Ping

2011-11-01

132

Volatilization of mercury compounds and utilization of various aromatic compounds by a broad-spectrum mercury resistant Bacillus pasteurii strain  

Microsoft Academic Search

Aquatic ecosystems may receive aromatic compounds through various routes. These compounds can cause cancerous diseases in aquatic animals and enhance mutagenicity of the sediments. The persistence of aromatic compounds deposited in sediments is affected by microbial degradation. Plasmid-determined mercuric and organomercurial resistance in microorganisms has also been studied by several workers. Utilization of various aromatic compounds as sole sources of

K. Pahan; S. Ray; R. Gachhui; J. Chaudhuri; A. Mandal

1991-01-01

133

Energy Efficiency in Western Utility Resource Plans: Impacts onRegional Resources Assessment and Support for WGA Policies  

SciTech Connect

In the aftermath of the consumer price shocks and short-term power shortages of the 2000-01 electricity crisis, policymakers and regulators in Western states are placing increased emphasis on integrated resource planning (IRP), resource adequacy and assessment and a diversified portfolio of resources to meet the needs of electricity consumers. In some states, this has led to a resurgence in state and utility commitments to energy efficiency. Increasing interest in acquiring energy efficiency as a power-system resource is also driven by the desire to dampen high growth rates in electricity demand in some Western states, rapid increases in natural gas prices, concerns about the environmental impacts of electricity generation (e.g. water consumption by power plants, air quality), and the potential of energy efficiency to provide utility bill savings for households and businesses (WGA CDEAC 2006). Recognizing the cost-competitiveness and environmental benefits of energy efficiency, the Western Governor's Association (WGA) has set a high priority for energy efficiency, establishing a goal of reducing projected electricity demand by 20% across the West by 2020 in a policy resolution on Clean and Diversified Energy for the West (WGA 2004). Nationally, the need for improved tracking of demand-side resources in load forecasting is formalized in the North American Electric Reliability Council (NERC)'s recently adopted reliability standards, which utilities and regional reliability organizations will need to comply with (NERC 2005a and 2005b). In this study, we examine the treatment of energy efficiency in recent resource plans issued by fourteen investor-owned utilities (IOUs) in the Western United States and Canada. The goals of this study are to: (1) summarize energy-efficiency resources as represented in a large sample of recent resource plans prepared by Western utilities and identify key issues; (2) evaluate the extent to which the information provided in current resource plans can be used to support region-wide resource assessment and tracking of state/utility progress in meeting the WGA's energy-efficiency goals (WGA 2004); and (3) offer recommendations on information and documentation of energy-efficiency resources that should be included in future resource plans to facilitate comparative review and regional coordination. The scope of this report covers projected electric end-use efficiency investments reported in all Western utility resource plans that were publicly available as of February 2006. While a few utilities included additional demand-side resources, such as demand response, in their plans, we do not report that information. However, many of the issues and recommendations in reference to energy efficiency in this report are relevant to other demand-side resources as well. This report is organized as follows. Section 2 outlines the data sources and approach used in this study and conceptualizes methods and metrics for tracking energy-efficiency resources over time. Section 3 presents results from the review of the utility resource plans. Important issues encountered in reviewing the resource plans are discussed in section 4. Finally, section 5 concludes with recommendations for improving the tracking and reporting of energy efficiency in forthcoming resource plans.

Hopper, Nicole; Goldman, Charles; Schlegal, Jeff

2006-08-01

134

U.S. utilities' experiences with the implementation of energy efficiency programs  

NASA Astrophysics Data System (ADS)

In the U.S., many electric utility companies are offering demand-side management (DSM) programs to their customers as ways to save money and energy. However, it is challenging to compare these programs between utility companies throughout the U.S. because of the variability of state energy policies. For example, some states in the U.S. have deregulated electricity markets and others do not. In addition, utility companies within a state differ depending on ownership and size. This study examines 12 utilities' experiences with DSM programs and compares the programs' annual energy savings results that the selected utilities reported to the Energy Information Administration (EIA). The 2009 EIA data suggests that DSM program effectiveness is not significantly affected by electricity market deregulation or utility ownership. However, DSM programs seem to generally be more effective when administered by utilities located in states with energy savings requirements and DSM program mandates.

Goss, Courtney

135

Design of a photostabilizer having built-in antioxidant functionality and its utility in obtaining broad-spectrum sunscreen formulations.  

PubMed

Di-2,2'-diethylhexyl-3,5-dimethoxy-4-hydroxy-benzylidenemalonate (INCI name diethylhexyl syringylidene malonate, DESM), the target photostabilizer, was synthesized in one step by condensation of 3,5-dimethoxy-4-hydroxy benzaldehyde (Syringaldehyde) with di-2,2'-diethylhexyl malonate. Photostability data in sunscreen formulations showed that DESM is photostable and improves the photostability of avobenzone significantly when compared to control (without a photostabilizer). Photostable broad-spectrum sunscreen formulations with high SPF (>30) have been achieved by combining avobenzone, DESM and UV-B sunscreens, such as homosalate, octisalate or other UV-B sunscreens. It seems that (a) triplet-state energy transfer from avobenzone to DESM and (b) scavenging of reactive species are responsible for the observed stabilization of avobenzone. In vitro study of the two formulations containing DESM clearly showed critical wavelength of well over 370 nm and can thus be categorized as broad-spectrum sunscreens. DESM does not have any contribution to in vivo SPF; instead it boosts SPF by about 5 units in high-SPF products. DESM was found to be an excellent singlet-oxygen quencher, thereby reducing photodegradation of avobenzone caused by singlet oxygen. In short, the multiplicity of effects and formulation benefits seen with DESM makes it an ideal choice as a unique antioxidant photostabilizer for a variety of cosmetic products targeting young and mature skin alike. PMID:16492073

Chaudhuri, Ratan K; Lascu, Zoia; Puccetti, Germain; Deshpande, Anant A; Paknikar, Sashikumar K

2006-01-01

136

Fuel Flexible Combustion Systems for High-Efficiency Utilization of Opportunity Fuels in Gas Turbines  

SciTech Connect

The purpose of this program was to develop low-emissions, efficient fuel-flexible combustion technology which enables operation of a given gas turbine on a wider range of opportunity fuels that lie outside of current natural gas-centered fuel specifications. The program encompasses a selection of important, representative fuels of opportunity for gas turbines with widely varying fundamental properties of combustion. The research program covers conceptual and detailed combustor design, fabrication, and testing of retrofitable and/or novel fuel-flexible gas turbine combustor hardware, specifically advanced fuel nozzle technology, at full-scale gas turbine combustor conditions. This project was performed over the period of October 2008 through September 2011 under Cooperative Agreement DE-FC26-08NT05868 for the U.S. Department of Energy/National Energy Technology Laboratory (USDOE/NETL) entitled "Fuel Flexible Combustion Systems for High-Efficiency Utilization of Opportunity Fuels in Gas Turbines". The overall objective of this program was met with great success. GE was able to successfully demonstrate the operability of two fuel-flexible combustion nozzles over a wide range of opportunity fuels at heavy-duty gas turbine conditions while meeting emissions goals. The GE MS6000B ("6B") gas turbine engine was chosen as the target platform for new fuel-flexible premixer development. Comprehensive conceptual design and analysis of new fuel-flexible premixing nozzles were undertaken. Gas turbine cycle models and detailed flow network models of the combustor provide the premixer conditions (temperature, pressure, pressure drops, velocities, and air flow splits) and illustrate the impact of widely varying fuel flow rates on the combustor. Detailed chemical kinetic mechanisms were employed to compare some fundamental combustion characteristics of the target fuels, including flame speeds and lean blow-out behavior. Perfectly premixed combustion experiments were conducted to provide experimental combustion data of our target fuels at gas turbine conditions. Based on an initial assessment of premixer design requirements and challenges, the most promising sub-scale premixer concepts were evaluated both experimentally and computationally. After comprehensive screening tests, two best performing concepts were scaled up for further development. High pressure single nozzle tests were performed with the scaled premixer concepts at target gas turbine conditions with opportunity fuels. Single-digit NOx emissions were demonstrated for syngas fuels. Plasma-assisted pilot technology was demonstrated to enhance ignition capability and provide additional flame stability margin to a standard premixing fuel nozzle. However, the impact of plasma on NOx emissions was observed to be unacceptable given the goals of this program and difficult to avoid.

Venkatesan, Krishna

2011-11-30

137

Efficient management and promotion of utilization of the video information acquired by observation  

NASA Astrophysics Data System (ADS)

In Japan Agency for Marine-Earth Science and Technology (JAMSTEC), the deep sea videos are made from the research by JAMSTEC submersibles in 1982, and the information on the huge deep-sea that will reach more 4,000 dives (ca. 24,700 tapes) by the present are opened to public via the Internet since 2002. The deep-sea videos is important because the time variation of deep-sea environment with difficult investigation and collection and growth of the living thing in extreme environment can be checked. Moreover, with development of video technique, the advanced analysis of an investigation image is attained. For grasp of deep sea environment, especially the utility value of the image is high. In JAMSTEC's Data Research Center for Marine-Earth Sciences (DrC), collection of the video are obtained by dive investigation of JAMSTEC, preservation, quality control, and open to public are performed. It is our big subject that the huge video information which utility value has expanded managed efficiently and promotion of use. In this announcement, the present measure is introduced about these subjects . The videos recorded on a tape or various media onboard are collected, and the backup and encoding for preventing the loss and degradation are performed. The video inside of a hard disk has the large file size. Then, we use the Linear Tape File System (LTFS) which attracts attention with image management engineering these days. Cost does not start compared with the usual disk backup, but correspondence years can also save the video data for a long time, and the operatively of a file is not different from a disk. The video that carried out the transcode to offer is archived by disk storage, and offer according to a use is possible for it. For the promotion of utilization of the video, the video public presentation system was reformed completely from November, 2011 to "JAMSTEC E-library of Deep Sea Images (http:// www.godac.jamstec.go.jp/jedi/)" This new system has preparing various searches (e.g. Search by map, Tree, Icon, Keyword et al.). The video annotation is enabled with the same interface, and the usability of use and management is raised. Moreover, In the "Biological Information System for Marine Life : BISMaL (http://www.godac.jamstec.go.jp/bismal/e/index.html)" which is a data system for biodiversity information, particularly in biogeographic data of marine organisms, based on photography position information, the visualization of living thing distribution, the life list of a deep sea living thing, and the deep sea video were used, and aim at the contribution to biodiversity grasp. Future, aiming at the accuracy improvement of the information given to the video by Work support of the comment registration by automatic recognition of an image and Development of a comment registration tool onboard, it aims at offering higher quality information.

Kitayama, T.; Tanaka, K.; Shimabukuro, R.; Hase, H.; Ogido, M.; Nakamura, M.; Saito, H.; Hanafusa, Y.; Sonoda, A.

2012-12-01

138

Improving yield potential in crops under elevated CO2: Integrating the photosynthetic and nitrogen utilization efficiencies  

PubMed Central

Increasing crop productivity to meet burgeoning human food demand is challenging under changing environmental conditions. Since industrial revolution atmospheric CO2 levels have linearly increased. Developing crop varieties with increased utilization of CO2 for photosynthesis is an urgent requirement to cope with the irreversible rise of atmospheric CO2 and achieve higher food production. The primary effects of elevated CO2 levels in most crop plants, particularly C3 plants, include increased biomass accumulation, although initial stimulation of net photosynthesis rate is only temporal and plants fail to sustain the maximal stimulation, a phenomenon known as photosynthesis acclimation. Despite this acclimation, grain yield is known to marginally increase under elevated CO2. The yield potential of C3 crops is limited by their capacity to exploit sufficient carbon. The “C fertilization” through elevated CO2 levels could potentially be used for substantial yield increase. Rubisco is the rate-limiting enzyme in photosynthesis and its activity is largely affected by atmospheric CO2 and nitrogen availability. In addition, maintenance of the C/N ratio is pivotal for various growth and development processes in plants governing yield and seed quality. For maximizing the benefits of elevated CO2, raising plant nitrogen pools will be necessary as part of maintaining an optimal C/N balance. In this review, we discuss potential causes for the stagnation in yield increases under elevated CO2 levels and explore possibilities to overcome this limitation by improved photosynthetic capacity and enhanced nitrogen use efficiency. Opportunities of engineering nitrogen uptake, assimilatory, and responsive genes are also discussed that could ensure optimal nitrogen allocation toward expanding source and sink tissues. This might avert photosynthetic acclimation partially or completely and drive for improved crop production under elevated CO2 levels.

Kant, Surya; Seneweera, Saman; Rodin, Joakim; Materne, Michael; Burch, David; Rothstein, Steven J.; Spangenberg, German

2012-01-01

139

Isolation and characterization of a mutant recombinant Saccharomyces cerevisiae strain with high efficiency xylose utilization.  

PubMed

A recombinant xylose-utilizing Saccharomyces cerevisiae strain carrying one copy of heterologous XYL1 and XYL2 from Pichia stipitis and endogenous XKS1 under the control of the TDH3 promoter in the chromosomal DNA was constructed from the industrial haploid yeast strain NAM34-4C, which showed thermotolerance and acid tolerance. The recombinant S. cerevisiae strain SCB7 grew in minimal medium containing xylose as the sole carbon source, and its shortest generation time (G(short)) was 5 h. From this strain, four mutants showing rapid growth (G(short) = 2.5 h) in the minimal medium were isolated. The mutants carried four mutations that were classified into three linkage groups. Three mutations were dominant and one mutation was recessive to the wild type allele. The recessive mutation was in the PHO13 gene encoding para-nitrophenyl phosphatase. The other mutant genes were not linked to TAL1 gene encoding transaldolase. When the mutants and their parental strain were used for the batch fermentation in a complex medium at pH 4.0 containing 30 g/L xylose at 35 °C with shaking (60 rpm) and an initial cell density (Absorbance at 660 nm) of 1.0, all mutants showed efficient ethanol production and xylose consumption from the early stage of the fermentation culture. In two mutants, within 24 h, 4.8 g/L ethanol was produced, and the ethanol yield was 47%, which was 1.4 times higher than that achieved with the parental strain. The xylose concentration in the medium containing the mutant decreased linearly at a rate of 1 g/L/h until 24 h. PMID:23810666

Tomitaka, Masataka; Taguchi, Hisataka; Fukuda, Kohsai; Akamatsu, Takashi; Kida, Kenji

2013-12-01

140

Improving yield potential in crops under elevated CO(2): Integrating the photosynthetic and nitrogen utilization efficiencies.  

PubMed

Increasing crop productivity to meet burgeoning human food demand is challenging under changing environmental conditions. Since industrial revolution atmospheric CO(2) levels have linearly increased. Developing crop varieties with increased utilization of CO(2) for photosynthesis is an urgent requirement to cope with the irreversible rise of atmospheric CO(2) and achieve higher food production. The primary effects of elevated CO(2) levels in most crop plants, particularly C(3) plants, include increased biomass accumulation, although initial stimulation of net photosynthesis rate is only temporal and plants fail to sustain the maximal stimulation, a phenomenon known as photosynthesis acclimation. Despite this acclimation, grain yield is known to marginally increase under elevated CO(2). The yield potential of C(3) crops is limited by their capacity to exploit sufficient carbon. The "C fertilization" through elevated CO(2) levels could potentially be used for substantial yield increase. Rubisco is the rate-limiting enzyme in photosynthesis and its activity is largely affected by atmospheric CO(2) and nitrogen availability. In addition, maintenance of the C/N ratio is pivotal for various growth and development processes in plants governing yield and seed quality. For maximizing the benefits of elevated CO(2), raising plant nitrogen pools will be necessary as part of maintaining an optimal C/N balance. In this review, we discuss potential causes for the stagnation in yield increases under elevated CO(2) levels and explore possibilities to overcome this limitation by improved photosynthetic capacity and enhanced nitrogen use efficiency. Opportunities of engineering nitrogen uptake, assimilatory, and responsive genes are also discussed that could ensure optimal nitrogen allocation toward expanding source and sink tissues. This might avert photosynthetic acclimation partially or completely and drive for improved crop production under elevated CO(2) levels. PMID:22833749

Kant, Surya; Seneweera, Saman; Rodin, Joakim; Materne, Michael; Burch, David; Rothstein, Steven J; Spangenberg, German

2012-01-01

141

The road to efficiency? Re-examining the impact of the primary care physician workforce on health care utilization rates  

Microsoft Academic Search

Research suggests that primary care physicians may help to control health care costs by encouraging more efficient service use. However, most studies do not account for data aggregation effects that can significantly affect the direction and magnitude of findings. To re-examine the association between the proportion of primary care physicians and health care utilization rates in an area, and investigate

David Bradley Wright; Thomas C. Ricketts III

2010-01-01

142

Interactions between Energy Efficiency Programs funded under the Recovery Act and Utility Customer-Funded Energy Efficiency Programs  

Microsoft Academic Search

Since the spring of 2009, billions of federal dollars have been allocated to state and local governments as grants for energy efficiency and renewable energy projects and programs. The scale of this American Reinvestment and Recovery Act (ARRA) funding, focused on 'shovel-ready' projects to create and retain jobs, is unprecedented. Thousands of newly funded players - cities, counties, states, and

Charles A. Goldman; Elizabeth Stuart; Ian Hoffman; Merrian C. Fuller; Megan A. Billingsley

2011-01-01

143

Increasing Diversity in Telecommunications Ownership and Increasing Efficiency in Spectrum Auctions by Breaking the Link Between Capital Market Discrimination and FCC Spectrum Auction Outcomes  

Microsoft Academic Search

In Section 309(j)4(D) of the Communications Act, the Federal Communications Commission (“FCC”) is required to increase opportunities\\u000a for minority groups to participate in the provision of spectrum based services. In Adarand Construction, Inc. v. Pena, the\\u000a Supreme Court held that race-based government programs were subject to strict scrutiny. That is race-based programs must serve\\u000a a compelling governmental interest such as remedying

Clarence Anthony Bush

2010-01-01

144

An International Approach to Re-Allocating Spectrum and Seeking New Efficiencies for Future Satellite Communications Frequency Use  

NASA Astrophysics Data System (ADS)

This paper repons on an internationally funded study supported by the Canadian Communications Research Centre (CRC), the Japanese Communications Research Lab (CRL), the European Space Agency (ESA) and the U.S. National Aeronautics and Space Administration (NASA) Funding of this study and provision of certain information to the international researchers should not be construed as explicit support for the results of this study. The study sponsors have, however, asked that the ITU explore new longer-term approaches to frequency allocation and to use the full report of the study team as an input to this study process. The objective of this study was to identify possible new ways to solve the problem of how to increase the throughput and quality of 21 st Century communications satellite systems while reducing the cost of service and aiding system availability To achieve this objective it is important to find a way to allocate frequencies to global users through a more effective process and to devise new ways to use spectrum more efficiently in both the technical and economic sense The various findings and recommendations of the study team with regard to accomplishing this objective are reported in the full report.

Pelton, Joseph N.; International Study Team

2000-07-01

145

Plasticity of rhizosphere hydraulic properties as a key for efficient utilization of scarce resources  

PubMed Central

Background It is known that the soil near roots, the so-called rhizosphere, has physical and chemical properties different from those of the bulk soil. Rhizosphere properties are the result of several processes: root and soil shrinking/swelling during drying/wetting cycles, soil compaction by root growth, mucilage exuded by root caps, interaction of mucilage with soil particles, mucilage shrinking/swelling and mucilage biodegradation. These processes may lead to variable rhizosphere properties, i.e. the presence of air-filled gaps between soil and roots; water repellence in the rhizosphere caused by drying of mucilage around the soil particles; or water accumulation in the rhizosphere due to the high water-holding capacity of mucilage. The resulting properties are not constant in time but they change as a function of soil condition, root growth rate and mucilage age. Scope We consider such a variability as an expression of rhizosphere plasticity, which may be a strategy for plants to control which part of the root system will have a facilitated access to water and which roots will be disconnected from the soil, for instance by air-filled gaps or by rhizosphere hydrophobicity. To describe such a dualism, we suggest classifying rhizosphere into two categories: class A refers to a rhizosphere covered with hydrated mucilage that optimally connects roots to soil and facilitates water uptake from dry soils. Class B refers to the case of air-filled gaps and/or hydrophobic rhizosphere, which isolate roots from the soil and may limit water uptake from the soil as well water loss to the soil. The main function of roots covered by class B will be long-distance transport of water. Outlook This concept has implications for soil and plant water relations at the plant scale. Root water uptake in dry conditions is expected to shift to regions covered with rhizosphere class A. On the other hand, hydraulic lift may be limited in regions covered with rhizosphere class B. New experimental methods need to be developed and applied to different plant species and soil types, in order to understand whether such dualism in rhizosphere properties is an important mechanism for efficient utilization of scarce resources and drought tolerance.

Carminati, Andrea; Vetterlein, Doris

2013-01-01

146

Multiplex ligation-dependent probe amplification for genetic screening in autism spectrum disorders: Efficient identification of known microduplications and identification of a novel microduplication in ASMT  

Microsoft Academic Search

BACKGROUND: It has previously been shown that specific microdeletions and microduplications, many of which also associated with cognitive impairment (CI), can present with autism spectrum disorders (ASDs). Multiplex ligation-dependent probe amplification (MLPA) represents an efficient method to screen for such recurrent microdeletions and microduplications. METHODS: In the current study, a total of 279 unrelated subjects ascertained for ASDs were screened

Guiqing Cai; Lisa Edelmann; Juliet E Goldsmith; Ninette Cohen; Alisa Nakamine; Jennifer G Reichert; Ellen J Hoffman; Danielle M Zurawiecki; Jeremy M Silverman; Eric Hollander; Latha Soorya; Evdokia Anagnostou; Catalina Betancur; Joseph D Buxbaum

2008-01-01

147

Utility and Performance Relative to Consumer-Product Energy-Efficiency Standards.  

National Technical Information Service (NTIS)

This interim report summarizes work done under the third of six tasks of an investigation of the relative utility and performance of nine consumer products covered by the Energy Policy and Conservation Act. Task III consisted of developing definitions and...

J. L. Coggins

1979-01-01

148

Design of an efficient Fresnel-type lens utilizing double total internal reflection for solar energy collection.  

PubMed

A novel of Fresnel-type lens for use as a solar collector has been designed which utilizes double total internal reflection (D-TIR) to optimize collection efficiency for high numerical aperture lenses (in the region of 0.3 to 0.6 NA). Results show that, depending on the numerical aperture and the size of the receiver, a collection efficiency theoretical improvement on the order of 20% can be expected with this new design compared with that of a conventional Fresnel lens. PMID:23326849

Wallhead, Ian; Jiménez, Teresa Molina; Ortiz, Jose Vicente García; Toledo, Ignacio Gonzalez; Toledo, Cristóbal Gonzalez

2012-11-01

149

Design of an efficient Fresnel-type lens utilizing double total internal reflection for solar energy collection.  

PubMed

A novel of Fresnel-type lens for use as a solar collector has been designed which utilizes double total internal reflection (D-TIR) to optimize collection efficiency for high numerical aperture lenses (in the region of 0.3 to 0.6 NA). Results show that, depending on the numerical aperture and the size of the receiver, a collection efficiency theoretical improvement on the order of 20% can be expected with this new design compared with that of a conventional Fresnel lens. PMID:23187651

Wallhead, Ian; Jiménez, Teresa Molina; Ortiz, Jose Vicente García; Toledo, Ignacio Gonzalez; Toledo, Cristóbal Gonzalez

2012-11-01

150

Combinatorial design of a highly efficient xylose-utilizing pathway in Saccharomyces cerevisiae for the production of cellulosic biofuels.  

PubMed

Balancing the flux of a heterologous metabolic pathway by tuning the expression and properties of the pathway enzymes is difficult, but it is critical to realizing the full potential of microbial biotechnology. One prominent example is the metabolic engineering of a Saccharomyces cerevisiae strain harboring a heterologous xylose-utilizing pathway for cellulosic-biofuel production, which remains a challenge even after decades of research. Here, we developed a combinatorial pathway-engineering approach to rapidly create a highly efficient xylose-utilizing pathway for ethanol production by exploring various combinations of enzyme homologues with different properties. A library of more than 8,000 xylose utilization pathways was generated using DNA assembler, followed by multitiered screening, which led to the identification of a number of strain-specific combinations of the enzymes for efficient conversion of xylose to ethanol. The balancing of metabolic flux through the xylose utilization pathway was demonstrated by a complete reversal of the major product from xylitol to ethanol with a similar yield and total by-product formation as low as 0.06 g/g xylose without compromising cell growth. The results also suggested that an optimal enzyme combination depends on not only the genotype/phenotype of the host strain, but also the sugar composition of the fermentation medium. This combinatorial approach should be applicable to any heterologous pathway and will be instrumental in the optimization of industrial production of value-added products. PMID:23183982

Kim, Byoungjin; Du, Jing; Eriksen, Dawn T; Zhao, Huimin

2013-02-01

151

Combinatorial Design of a Highly Efficient Xylose-Utilizing Pathway in Saccharomyces cerevisiae for the Production of Cellulosic Biofuels  

PubMed Central

Balancing the flux of a heterologous metabolic pathway by tuning the expression and properties of the pathway enzymes is difficult, but it is critical to realizing the full potential of microbial biotechnology. One prominent example is the metabolic engineering of a Saccharomyces cerevisiae strain harboring a heterologous xylose-utilizing pathway for cellulosic-biofuel production, which remains a challenge even after decades of research. Here, we developed a combinatorial pathway-engineering approach to rapidly create a highly efficient xylose-utilizing pathway for ethanol production by exploring various combinations of enzyme homologues with different properties. A library of more than 8,000 xylose utilization pathways was generated using DNA assembler, followed by multitiered screening, which led to the identification of a number of strain-specific combinations of the enzymes for efficient conversion of xylose to ethanol. The balancing of metabolic flux through the xylose utilization pathway was demonstrated by a complete reversal of the major product from xylitol to ethanol with a similar yield and total by-product formation as low as 0.06 g/g xylose without compromising cell growth. The results also suggested that an optimal enzyme combination depends on not only the genotype/phenotype of the host strain, but also the sugar composition of the fermentation medium. This combinatorial approach should be applicable to any heterologous pathway and will be instrumental in the optimization of industrial production of value-added products.

Kim, Byoungjin; Du, Jing; Eriksen, Dawn T.

2013-01-01

152

Reserves for improving the utilization efficiency of regenerative extractions from turbines at cogeneration stations  

NASA Astrophysics Data System (ADS)

It is shown that considerable reserves for improving energy efficiency are available at the majority of Russian cogeneration stations, because the arrangements using which heat is supplied for the needs of water treatment plants are far from being optimal. New solutions are proposed that allow heat to be supplied to these loads in a more economically efficient manner with the use of low-potential regenerative extractions from cogeneration steam turbines, as well as technologies for improving the efficiency of combined-cycle plants the exhaust gases from which are discharged into a boiler.

Zamaleev, M. M.; Sharapov, V. I.

2008-04-01

153

Impact of Large Scale Energy Efficiency Programs On Consumer Tariffs and Utility Finances in India  

SciTech Connect

Large-scale EE programs would modestly increase tariffs but reduce consumers' electricity bills significantly. However, the primary benefit of EE programs is a significant reduction in power shortages, which might make these programs politically acceptable even if tariffs increase. To increase political support, utilities could pursue programs that would result in minimal tariff increases. This can be achieved in four ways: (a) focus only on low-cost programs (such as replacing electric water heaters with gas water heaters); (b) sell power conserved through the EE program to the market at a price higher than the cost of peak power purchase; (c) focus on programs where a partial utility subsidy of incremental capital cost might work and (d) increase the number of participant consumers by offering a basket of EE programs to fit all consumer subcategories and tariff tiers. Large scale EE programs can result in consistently negative cash flows and significantly erode the utility's overall profitability. In case the utility is facing shortages, the cash flow is very sensitive to the marginal tariff of the unmet demand. This will have an important bearing on the choice of EE programs in Indian states where low-paying rural and agricultural consumers form the majority of the unmet demand. These findings clearly call for a flexible, sustainable solution to the cash-flow management issue. One option is to include a mechanism like FAC in the utility incentive mechanism. Another sustainable solution might be to have the net program cost and revenue loss built into utility's revenue requirement and thus into consumer tariffs up front. However, the latter approach requires institutionalization of EE as a resource. The utility incentive mechanisms would be able to address the utility disincentive of forgone long-run return but have a minor impact on consumer benefits. Fundamentally, providing incentives for EE programs to make them comparable to supply-side investments is a way of moving the electricity sector toward a model focused on providing energy services rather than providing electricity.

Abhyankar, Nikit; Phadke, Amol

2011-01-20

154

Determination of Richard B. Russell Dissolved Oxygen Injection System Efficiency Utilizing Automated Remote Monitoring Technologies.  

National Technical Information Service (NTIS)

Studies to determine the effectiveness and efficiency of an oxygen injection system were conducted at Richard B. Russell Dam and Lake in 1995. Studies were conducted by deploying an array of automated water quality logging instruments upstream and downstr...

J. W. Lemons M. C. Vorwerk J. H. Carroll

1998-01-01

155

Genome Sequence of Bacillus cereus Strain A1, an Efficient Starch-Utilizing Producer of Hydrogen  

PubMed Central

Bacillus cereus strain A1 is a newly isolated hydrogen producer capable of utilizing bioresources and biowaste, such as starch and starch wastewater. Here, we present a 5.67-Mb assembly of the genome sequence of strain A1, which may provide insights into the molecular mechanism of hydrogen production from bioresources and biowaste.

Zhang, Ting; Bao, Meidan; Wang, Yu; Tan, Tianwei

2014-01-01

156

High-Efficiency Multi-Junction Space Solar Development Utilizing Lattice Grading  

NASA Technical Reports Server (NTRS)

Progress towards achieving a high one-sun air mass 0 (AM0) efficiency in a monolithic dual junction solar cell comprised of a 1.62 eV InGaP top cell and a 1.1 eV InGaAs bottom cell grown on buffered GaAs is reported. The performance of stand-alone 1.62 eV InGaP and 1.1 eV InGaAs cells is compared to that of the dual junction cell. Projected AM0 efficiencies of 15.7% and 16.5% are expected for the 1.62 eV InGaP and 1.1 eV InGaAs cells grown on buffered GaAs. The dual junction cell has a projected one-sun AM0 conversion efficiency of 17%. The projected efficiencies are based upon the application of an optimized anti-reflective coating (ARC) to the as-grown cells. Quantum efficiency (QE) data obtained from the dual junction cell indicate that is is bottom cell current limited with the top cell generating 50% more current than the bottom cell. A comparison of the QE data for the stand-alone 1.1 eV InGaAs cell to that of the 1.1 eV InGaAs bottom cell in the tandem configuration indicates a degradation of the bottom cell conversion efficiency in the tandem configuration. The origin of this performance degradation is at present unknown. If the present limitation can be overcome, then a one-sun AM0 efficiency of 26% is achievable with the 1.62 eV/1.1 eV dual junction cell grown lattice-mismatched to GaAs.

Stan, Mark A.; Weizer, Victor G.; Pal, AnnaMaria; Garverick, Linda M.; Khan, Osman; Sinharoy, Samar; Hoffman, Richard W., Jr.; Jenkins, Phillip P.; Scheiman, David A.; Fatemi, Navid S.

2005-01-01

157

Jicarilla Apache Utility Authority Renewable Energy and Energy Efficiency Strategic Planning  

SciTech Connect

The purpose of this Strategic Plan Report is to provide an introduction and in-depth analysis of the issues and opportunities, resources, and technologies of energy efficiency and renewable energy that have potential beneficial application for the people of the Jicarilla Apache Nation and surrounding communities. The Report seeks to draw on the best available information that existed at the time of writing, and where necessary, draws on new research to assess this potential. This study provides a strategic assessment of opportunities for maximizing the potential for electrical energy efficiency and renewable energy development by the Jicarilla Apache Nation. The report analyzes electricity use on the Jicarilla Apache Reservation in buildings. The report also assesses particular resources and technologies in detail, including energy efficiency, solar, wind, geothermal, biomass, and small hydropower. The closing sections set out the elements of a multi-year, multi-phase strategy for development of resources to the maximum benefit of the Nation.

Rabago, K.R.

2008-06-28

158

Analysis of power sector efficiency improvements for an integrated utility planning process in Costa Rica  

SciTech Connect

In an effort to analyze and document the potential for power sector efficiency improvements from generation to end-use, the Agency for International Development and the Government of Costa Rica are jointly conducting an integrated power sector efficiency analysis. Potential for energy and cost savings in power plants, transmission and distribution, and demand-side management programs are being evaluated. The product of this study will be an integrated investment plan for the Instituto Costarricense de Electricidad, incorporating both supply and demand side investment options. This paper presents the methodology employed in the study, as well as preliminary estimates of the results of the study. 14 refs., 4 figs., 5 tabs.

Waddle, D.B.; MacDonald, J.M.

1990-01-01

159

Efficient utilization of red maple lumber in glued-laminated timber beams. Forest Service research paper  

Microsoft Academic Search

The feasibility of utilizing cant-sawn hardwood lumber, which would not usually be desired for furniture manufacture, was studied for the manufacture of structural glue-laminated (glulam) timber. Two red maple beam combinations were evaluated. Test results of 42 red maple glulam beams showed that it was feasible to develop structural glulam timber from cant-swan lumber. The glulam combinations made from E-rated

J. J. Janowiak; H. B. Manbeck; R. Hernandez; R. C. Moody; P. R. Blankenhorn

1995-01-01

160

Utility-function-driven energy-efficient cooling in data centers  

Microsoft Academic Search

The sharp rise in energy usage in data centers, fueled by increased IT workload and high server density, and coupled with a concomitant increase in the cost and volatility of the energy supply, have triggered urgent calls to improve data center energy efficiency. In response, researchers have developed energy-aware IT systems that slow or shut down servers without sacrificing performance

Rajarshi Das; Jeffrey O. Kephart; Jonathan Lenchner; Hendrik Hamann

2010-01-01

161

Jumbo Store: Providing Efficient Incremental Upload and Versioning for a Utility Rendering Service  

Microsoft Academic Search

We have developed a new storage system called the Jumbo Store (JS) based on encoding directory tree snapshots as graphs called HDAGs whose nodes are small variable-length chunks of data and whose edges are hash pointers. We store or transmit each node only once and encode using landmark-based chunking plus some new tricks. This leads to very efficient incremental upload

Kave Eshghi; Mark Lillibridge; Lawrence Wilcock; Guillaume Belrose; Rycharde Hawkes

2007-01-01

162

Energy Efficient Information Dissemination in Ad Hoc Networks Utilizing Bi-orthogonal Signaling  

Microsoft Academic Search

In this paper, we leverage bi-orthogonal signaling by using a time slot dependent identification scheme that enables energy efficient information dissemination, independent of the network topology. The ap- proach, although motivated by cooperative modulation schemes that re- quire information to be dispersed to other nodes within a wireless ad hoc network, can be applied directly to wired networks. As a

C. M. Okino; Esther H. Jennings

2002-01-01

163

Measuring Airport Efficiency with Fixed Asset Utilization to Minimize Airport Delays  

Microsoft Academic Search

Deregulation of the airlines in the United States spawned a free-for-all system which led to a variety of agents within the aviation system all seeking to optimize their own piece of the aviation system, and the net result was that the aviation system itself was not optimized in aggregate, frequently resulting in delays. Research on the efficiency of the system

Scott D. Widener

2010-01-01

164

Efficiency of Nitrogen Fertilizer for Potato under Fertigation Utilizing a Nitrogen Tracer Technique  

Microsoft Academic Search

Efficient crop use of nitrogen (N) fertilizer is critical from economic and environmental viewpoints, especially under irrigated conditions. Nitrogen fertilizer (N?labeled urea) and irrigation methods (drip and furrow) were evaluated on spring and fall potato cultivars under Syrian Mediterranean climatic conditions. Field experiments were conducted in the El?Ghab Valley near Hama in fall 2000 and spring 2001 on a heavy

Mussaddak Janat

2007-01-01

165

A ROBUST ABSOLUTE DETECTION EFFICIENCY CALIBRATION METHOD UTILIZING BETA/GAMMA COINCIDENCE SIGNATURES AND ISOTOPICALLY PURIFIED NEUTRON ACTIVATED RADIOXENON ISOTOPES  

SciTech Connect

Efforts to calibrate the absolute efficiency of gas cell radiations detectors have utilized a number of methodologies which allow adequate calibration but are time consuming and prone to a host of difficult-to-determine uncertainties. A method that extrapolates the total source strength from the measured beta and gamma gated beta coincidence signal was developed in the 1960’s and 1970’s. It has become clear that it is possible to achieve more consistent results across a range of isotopes and a range of activities using this method. Even more compelling is the ease with which this process can be used on routine samples to determine the total activity present in the detector. Additionally, recent advances in the generation of isotopically pure radioxenon samples of Xe-131m, Xe-133, and Xe-135 have allowed these measurement techniques to achieve much better results than would have been possible before when using mixed isotopic radioxenon source. This paper will discuss the beta/gamma absolute detection efficiency technique that utilizes several of the beta-gamma decay signatures to more precisely determine the beta and gamma efficiencies. It will than compare these results with other methods using pure sources of Xe-133, Xe-131m, and Xe-135 and a Xe-133/Xe-133m mix.

McIntyre, Justin I.; Cooper, Matthew W.; Ely, James H.; Haas, Derek A.; Schrom, Brian T.

2012-09-21

166

Efficient utilization of red maple lumber in glued-laminated timber beams. Forest Service research paper  

SciTech Connect

The feasibility of utilizing cant-sawn hardwood lumber, which would not usually be desired for furniture manufacture, was studied for the manufacture of structural glue-laminated (glulam) timber. Two red maple beam combinations were evaluated. Test results of 42 red maple glulam beams showed that it was feasible to develop structural glulam timber from cant-swan lumber. The glulam combinations made from E-rated lumber exceeded the target design bending stress of 2,400 lb/in 2 and met the target modulus of elasticity (MOE) of 1.8 x 106 lb/in 2.

Janowiak, J.J.; Manbeck, H.B.; Hernandez, R.; Moody, R.C.; Blankenhorn, P.R.

1995-09-01

167

Development of a highly efficient brushless dc motor utilizing both radial and axial air gaps  

NASA Astrophysics Data System (ADS)

This research proposes an effective structure for a brushless dc motor utilizing both radial and axial air gaps. The proposed motor generates torque in both the radial and axial air gaps, while the conventional motor generates torque only in the radial air gap. The proposed motor was optimized to minimize the electromagnetic loss of the motor to increase the effective air gap length and fill-factor of the coil while decreasing the saturation of the core at the same time. The electromagnetic loss was reduced by 35% in comparison with a conventional motor.

Kang, K. J.; Jang, G. H.; Sung, S. J.; Chang, J. H.

2012-04-01

168

Pumping iron to keep fit: modulation of siderophore secretion helps efficient aromatic utilization in Pseudomonas putida KT2440.  

PubMed

Studies of biotechnology applications of Pseudomonas putida KT2440 have been predominantly focused on regulation and expression of the toluene degradation (TOL) pathway. Unfortunately, there is limited information on the role of other physiological factors influencing aromatic utilization. In this report, we demonstrate that P. putida KT2440 increases its siderophore secretion in response to the availability of benzyl alcohol, a model aromatic substrate. It is argued that accelerated siderophore secretion in response to aromatic substrates provides an iron 'boost' which is required for the effective functioning of the iron-dependent oxygenases responsible for ring opening. Direct evidence for the cardinal role of siderophores in aromatic utilization is provided by evaluation of per capita siderophore secretion and comparative growth assessments of wild-type and siderophore-negative mutant strains grown on an alternative carbon source. Accelerated siderophore secretion can be viewed as a compensatory mechanism in P. putida in the context of its inability to secrete more than one type of siderophore (pyoverdine) or to utilize heterologous siderophores. Stimulated siderophore secretion might be a key factor in successful integration and proliferation of this organism as a bio-augmentation agent for aromatic degradation. It not only facilitates efficient aromatic utilization, but also provides better opportunities for iron assimilation amongst diverse microbial communities, thereby ensuring better survival and proliferation. PMID:24742959

Joshi, Hiren; Dave, Rachna; Venugopalan, V P

2014-07-01

169

Fast rotation invariant 3D feature computation utilizing efficient local neighborhood operators.  

PubMed

We present a method for densely computing local rotation invariant image descriptors in volumetric images. The descriptors are based on a transformation to the harmonic domain, which we compute very efficiently via differential operators. We show that this fast voxelwise computation is restricted to a family of basis functions that have certain differential relationships. Building upon this finding, we propose local descriptors based on the Gaussian Laguerre and spherical Gabor basis functions and show how the coefficients can be computed efficiently by recursive differentiation. We exemplarily demonstrate the effectiveness of such dense descriptors in a detection and classification task on biological 3D images. In a direct comparison to existing volumetric features, among them 3D SIFT, our descriptors reveal superior performance. PMID:22201055

Skibbe, Henrik; Reisert, Marco; Schmidt, Thorsten; Brox, Thomas; Ronneberger, Olaf; Burkhardt, Hans

2012-08-01

170

Sugar transporters in efficient utilization of mixed sugar substrates: current knowledge and outlook  

Microsoft Academic Search

There is increasing interest in production of transportation fuels and commodity chemicals from lignocellulosic biomass, most\\u000a desirably through biological fermentation. Considerable effort has been expended to develop efficient biocatalysts that convert\\u000a sugars derived from lignocellulose directly to value-added products. Glucose, the building block of cellulose, is the most\\u000a suitable fermentation substrate for industrial microorganisms such as Escherichia coli, Corynebacterium glutamicum,

Toru Jojima; Crispinus A. Omumasaba; Masayuki Inui; Hideaki Yukawa

2010-01-01

171

Differing efficiencies of potassium utilization in strains of Snapbeans, Phaseolus Vulgaris L  

Microsoft Academic Search

Summary The capacities of sixty-six strains of snapbeans to grow in potassium-deficient media were compared in nutrient culture experiments. Marked differences were observed, particularly in the severity of potassium-deficiency symptoms. From this initial screening, two of the most efficient strains and three of the most inefficient were selected for detailed nutritional and genetic studies. The unusual capacity of some strains

P. F. Shea; G. C. Gerloff; W. H. Gabelman

1968-01-01

172

Process Improvement Methods Increase the Efficiency, Accuracy and Utility of a Neurocritical Care Research Repository  

PubMed Central

Background Reliable and efficient data repositories are essential for the advancement of research in Neurocritical care. Various factors, such as the large volume of patients treated within the Neuro ICU, their differing length and complexity of hospital stay and the substantial amount of desired information can complicate the process of data collection. Methods We adapted the tools of process improvement to the data collection and database design of a research repository for a Neuroscience intensive care unit. Using the Shewhart-Deming method, we implemented an iterative approach to improve the process of data collection for each element. After an initial design phase, we re-evaluated all data fields that were challenging or time-consuming to collect. We then applied root-cause analysis to optimize the accuracy and ease of collection, and to determine the most efficient manner of collecting the maximal amount of data. Results During a six month period, we iteratively analyzed the process of data collection for various data elements. For example, the pre-admission medications were found to contain numerous inaccuracies after comparison with a gold standard (sensitivity 71% and specificity 94%). Also, our first method of tracking patient admissions and discharges contained higher than expected errors (sensitivity 94% and specificity 93%). In addition to increasing accuracy, we focused on improving efficiency. Through repeated incremental improvements, we reduced the number of subject records that required daily monitoring from 40 to 6 per day, and decreased daily effort from 4.5 to 1.5 hours per day. Conclusions By applying process improvement methods to the design of a Neuroscience ICU data repository, we achieved a three-fold improvement in efficiency and increased accuracy. Although individual barriers to data collection will vary from institution to institution, a focus on process improvement is critical to overcoming these barriers.

O'Connor, Sydney; Ayres, Alison; Cortellini, Lynelle; Rosand, Jonathan; Rosenthal, Eric; Kimberly, W. Taylor

2012-01-01

173

Evaluation of Energy Saving Characteristics of a High-Efficient Cogeneration System Utilizing Gas Engine Exhaust Heat  

NASA Astrophysics Data System (ADS)

A high efficiency cogeneration system (CGS) utilizing high temperature exhaust gas from a gas engine is proposed. In the proposed CGS, saturated steam produced in the gas engine is superheated with a super heater utilizing regenerative burner and used to drive a steam turbine generator. The heat energy is supplied by extracting steam from the steam turbine and turbine outlet low-temperature steam. Both of the energy saving characteristics of the proposed CGS and a CGS constructed by using the original gas engine (GE-CGS) were investigated and compared, by taking a case where energy for office buildings was supplied by the conventional energy systems. It was shown that the proposed CGS has energy saving rate of 24.5%, higher than 1.83 times, compared with that of the original GE-CGS.

Pak, Pyong Sik

174

The Utilization of HOPG based Graphene for a less costly and efficient replacement of platinum in Dye-Sensitized Solar Cells (DSC's)  

NASA Astrophysics Data System (ADS)

Dye-Sensitized Solar Cells (DSC) are also known as Graetzel cells after their inventor, Michael Graetzel, who invented them in 1991. DSCs are potential alternatives to the more conventional and expensive semiconductor p-n junction solar cells like silicon solar cells. In a Graetzel cell, light is absorbed by a sensitizing dye which is coupled to a wide band gap semiconductor (TiO2). Electric charges are liberated by the photon induced electron injection from the dye molecules into the conduction band of the semiconductor. The use of sensitizers in conjunction with the semiconductor oxide permits the absorption of a large portion of the terrestrial solar spectrum with near 10% conversion efficiency. In the ``traditional'' DSC, platinum metal is used as one of the counter electrode materials. In our research, graphene of various forms (from HOPG in specific) is utilized instead of costly platinum to replace the counter-electrode in the DSC's. HOPG also known as Higly Oriented Pyrolitic Graphite is being used to dry deposit graphene layers onto glass or FTO.

Pusko, Matthew P.

2012-10-01

175

Phase III Advanced Anodes and Cathodes Utilized in Energy Efficient Aluminum Production Cells  

SciTech Connect

During Phase I of the present program, Alcoa developed a commercial cell concept that has been estimated to save 30% of the energy required for aluminum smelting. Phase ii involved the construction of a pilot facility and operation of two pilots. Phase iii of the Advanced Anodes and Cathodes Program was aimed at bench experiments to permit the resolution of certain questions to be followed by three pilot cells. All of the milestones related to materials, in particular metal purity, were attained with distinct improvements over work in previous phases of the program. NiO additions to the ceramic phase and Ag additions to the Cu metal phase of the cermet improved corrosion resistance sufficiently that the bench scale pencil anodes met the purity milestones. Some excellent metal purity results have been obtained with anodes of the following composition: Further improvements in anode material composition appear to be dependent on a better understanding of oxide solubilities in molten cryolite. For that reason, work was commissioned with an outside consultant to model the MeO - cryolite systems. That work has led to a better understanding of which oxides can be used to substitute into the NiO-Fe2O3 ceramic phase to stabilize the ferrites and reduce their solubility in molten cryolite. An extensive number of vertical plate bench electrolysis cells were run to try to find conditions where high current efficiencies could be attained. TiB2-G plates were very inconsistent and led to poor wetting and drainage. Pure TiB2 did produce good current efficiencies at small overlaps (shadowing) between the anodes and cathodes. This bench work with vertical plate anodes and cathodes reinforced the importance of good cathode wetting to attain high current efficiencies. Because of those conclusions, new wetting work was commissioned and became a major component of the research during the third year of Phase III. While significant progress was made in several areas, much work needs to be done. The anode composition needs further improvements to attain commercial purity targets. At the present corrosion rate, the vertical plate anodes will wear too rapidly leading to a rapidly increasing anode-cathode gap and thermal instabilities in the cell. Cathode wetting as a function of both cathode plate composition and bath composition needs to be better understood to ensure that complete drainage of the molten aluminum off the plates occurs. Metal buildup appears to lead to back reaction and low current efficiencies.

R.A. Christini; R.K. Dawless; S.P. Ray; D.A. Weirauch, Jr.

2001-11-05

176

The 58-kilodalton major virulence factor of Francisella tularensis is required for efficient utilization of iron.  

PubMed

We investigated the role of the 58-kDa FTT0918 protein in the iron metabolism of Francisella tularensis. The phenotypes of SCHU S4, a prototypic strain of F. tularensis subsp. tularensis, and the Delta FTT0918 and Delta fslA isogenic mutants were analyzed. The gene product missing in the Delta fslA mutant is responsible for synthesis of a siderophore. When grown in broth with various iron concentrations, the two deletion mutants generally reached lower maximal densities than SCHU S4. The Delta FTT0918 mutant, but not the Delta fslA mutant, upregulated the genes of the F. tularensis siderophore locus (fsl) operon even at high iron concentrations. A chrome azurol sulfonate plate assay confirmed siderophore production by all strains except the Delta fslA strain. In a cross-feeding experiment using medium devoid of free iron, SCHU S4 promoted growth of the Delta fslA strain but not of the Delta FTT0918 strain. The sensitivity of SCHU S4 and the Delta FTT0918 and Delta fslA strains to streptonigrin demonstrated that the Delta FTT0918 strain contained a smaller free intracellular iron pool and that the Delta fslA strain contained a larger one than SCHU S4. In contrast to the marked attenuation of the Delta FTT0918 strain, the Delta fslA strain was as virulent as SCHU S4 in a mouse model. Altogether, the data demonstrate that the FTT0918 protein is required for F. tularensis to utilize iron bound to siderophores and that it likely has a role also in siderophore-independent iron acquisition. We suggest that the FTT0918 protein be designated Fe utilization protein A, FupA. PMID:19651867

Lindgren, Helena; Honn, Marie; Golovlev, Igor; Kadzhaev, Konstantin; Conlan, Wayne; Sjöstedt, Anders

2009-10-01

177

High-efficiency green organic light-emitting devices utilizing phosphorescent bis-cyclometalated alkynylgold(III) complexes.  

PubMed

A new phosphorescent material of cyclometalated alkynylgold(III) complex, [Au(2,5-F(2)C(6)H(3)-C?N?C)(C?C-C(6)H(4)N(C(6)H(5))(2)-p)] (1) (2,5-F(2)C(6)H(3)-HC?N?CH = 2,6-diphenyl-4-(2,5-difluorophenyl)pyridine), has been synthesized, characterized, and its device performance investigated. This luminescent gold(III) complex was found to exhibit rich PL and EL properties and has been utilized as phosphorescent dopants of OLEDs. At an optimized dopant concentration of 4%, a device with a maximum external quantum efficiency (EQE) of 11.5%, corresponding to a current efficiency of 37.4 cd/A and a power efficiency of 26.2 lm/W, has been obtained. Such a high EQE is comparable to that of Ir(ppy)(3)-based devices. The present work suggests that the alkynylgold(III) complex is a promising phosphorescent material in terms of both efficiency and thermal stability, with the additional advantages of its relatively inexpensive cost and low toxicity. PMID:20849118

Au, Vonika Ka-Man; Wong, Keith Man-Chung; Tsang, Daniel Ping-Kuen; Chan, Mei-Yee; Zhu, Nianyong; Yam, Vivian Wing-Wah

2010-10-13

178

Comparison of the cutting efficiency of two ultrasonic units utilizing two different tips at two different power settings.  

PubMed

The objective of this in vitro study was to set up a testing protocol and utilize it to evaluate and compare the cutting efficiency of ultrasonic units. Evaluation of two ultrasonic units utilizing two different tips was done by measuring the weght of a dentin specimen before and after ultrasonic treatment for set time periods. The difference in weight was the amount of dentin removed. The ultrasonic units tested were the P5 Booster (Staelec, France) and the Spartan (Obtura-Spartan, Fenton, MO) machines. The tips tested were the CPR-2D and ETD20 types. The units were tested at maximum and medium power. All the experimental variables, ultrasonic unit type, power setting and tip type were found to have an effect on the cutting efficiency (P<0.0001). The P5 ultrasonic unit was more effective at dentin removal than the Spantan ultrasonic unit at both power settings. The ETD-20 tip was more effective at dentin removal than the CPR-2D tip on both units at both power settings. PMID:16249728

Paz, Ernesto; Satovsky, James; Moldauer, Ivan

2005-11-01

179

Tricaproin, tricaprin and trilaurin are utilized more efficiently than tricaprylin by carp (Cyprinus carpio L.) larvae.  

PubMed

We investigated the effect of chain length of dietary medium-chain fatty acids (MCFA) on growth performance and fatty acid composition of first-feeding carp larvae. In a first trial, five semi-purified isolipidic (23-24 g/100 g of dry matter) diets were formulated to contain either 10 g/100 g triolein (control diet) or 5 g/100 g triolein and 5 g/100 g medium-chain triacylglycerols (MCT) supplied as tricaproin, tricaprylin, tricaprin or trilaurin. After 21 d, survival and growth rates were significantly greater in larvae fed diets containing triolein, tricaproin, tricaprin and trilaurin (final survival: 92 +/- 7% and mean larval weight: 42 +/- 15 mg) than in larvae fed tricaprylin (final survival: 56 +/- 12% and mean larval weight: 15 +/- 1 mg). The recovered levels of the fed MCFA in larval total lipids were respectively 0, 1.3, 7.3 and 8.1 g/100 g of total fatty acids. In a second trial, two isolipidic (18 g/100 g) diets containing 10 g/100 g triolein or tricaprylin were tested. High amounts of capric acid (up to 25 g/100 g of total fatty acids) were found in neutral lipids of carp larvae fed tricaprylin for 11 d, suggesting an unusual elongation of caprylic acid. This study underlines the peculiarity of tricaprylin among other MCT which seem well utilized up to 20-30 g/100 g of total dietary fatty acids. The exception of tricaprylin raises the question of the metabolic pathways followed by this MCT, especially for the suggested direct elongation of caprylic acid into capric acid. PMID:10917917

Fontagné, S; Corraze, G; Bergot, P

2000-08-01

180

Collision Efficiency of Drops in a Wide Range of Reynolds Numbers: Effects of Pressure on Spectrum Evolution  

Microsoft Academic Search

suitable for drops with radii ranging from 40 to 300 m.The collision efficiency and the collision kernel are calculated at different heights of 1000, 750, and 500 mb. It is shown that both the collision efficiencies and the collision kernel significantly increase with height. This increase of the collision kernel is by 90% caused by the increase in the collision

M. Pinsky; A. Khain; M. Shapiro

2001-01-01

181

An efficient grid layout algorithm for biological networks utilizing various biological attributes  

PubMed Central

Background Clearly visualized biopathways provide a great help in understanding biological systems. However, manual drawing of large-scale biopathways is time consuming. We proposed a grid layout algorithm that can handle gene-regulatory networks and signal transduction pathways by considering edge-edge crossing, node-edge crossing, distance measure between nodes, and subcellular localization information from Gene Ontology. Consequently, the layout algorithm succeeded in drastically reducing these crossings in the apoptosis model. However, for larger-scale networks, we encountered three problems: (i) the initial layout is often very far from any local optimum because nodes are initially placed at random, (ii) from a biological viewpoint, human layouts still exceed automatic layouts in understanding because except subcellular localization, it does not fully utilize biological information of pathways, and (iii) it employs a local search strategy in which the neighborhood is obtained by moving one node at each step, and automatic layouts suggest that simultaneous movements of multiple nodes are necessary for better layouts, while such extension may face worsening the time complexity. Results We propose a new grid layout algorithm. To address problem (i), we devised a new force-directed algorithm whose output is suitable as the initial layout. For (ii), we considered that an appropriate alignment of nodes having the same biological attribute is one of the most important factors of the comprehension, and we defined a new score function that gives an advantage to such configurations. For solving problem (iii), we developed a search strategy that considers swapping nodes as well as moving a node, while keeping the order of the time complexity. Though a naïve implementation increases by one order, the time complexity, we solved this difficulty by devising a method that caches differences between scores of a layout and its possible updates. Conclusion Layouts of the new grid layout algorithm are compared with that of the previous algorithm and human layout in an endothelial cell model, three times as large as the apoptosis model. The total cost of the result from the new grid layout algorithm is similar to that of the human layout. In addition, its convergence time is drastically reduced (40% reduction).

Kojima, Kaname; Nagasaki, Masao; Jeong, Euna; Kato, Mitsuru; Miyano, Satoru

2007-01-01

182

INDUCED NONENZYMATIC BROWNING OF SOYBEAN MEAL. III. DIGESTIBILITY AND EFFICIENCY OF PROTEIN UTILIZATION BY RUMINANTS OF SOYBEAN MEAL TREATED WITH XYLOSE OR GLUCOSE 1  

Microsoft Academic Search

Trials were conducted to evaluate effects of non-enzymatic browning of soybean meal (SBM) on efficiency of protein utilization and N digestibility. In trial 1, 48 Suffolk-Finnsheep lambs (22 kg) were fed 80 d to evaluate efficiency of protein utilization for growth when supplemental protein was fed as urea (U), commercial SBM (CS), or commercial SBM (pH 8.5, 83% dry matter)

R. M. Cleale; T. J. Klopfenstein; R. A. Britton; L. D. Satterlee; S. R. Lowry

2010-01-01

183

Utilizing Mass Measurements in Tracer Studies - A Systematic Approach to Efficient Modeling  

PubMed Central

Tracer enrichment data are fitted by multicompartmental models to estimate rate constants and fluxes or transport rates. In apolipoprotein turnover studies, mass measurements are also available, e.g., apolipoprotein B (apoB) levels in VLDL, IDL and LDL, and are often essential to calculate some of the rate constants. The usual method to use mass measurements is to estimate pool masses along with rate constants. A systematic alternative approach is developed to use flux balances around pools to express some rate constants in terms of the other rate constants and the measured masses. The resulting reduction in the number of parameters to be estimated makes the modeling more efficient. In models that would be unidentifiable without mass measurements, the usual approach and the proposed approach yield identical results. In a simple two-pool model, the number of unknown parameters is reduced from four to two. In a published 5-pool model for apoB kinetics with three mass measurements, the number of parameters is reduced from 12 to 9. With m mass measurements, the number of responses to be fitted and the number of parameters to be estimated are each reduced by m, a simplification by 1/4 to 1/3 in a typical pool model. Besides a proportionate reduction in computational effort, there is a further benefit since the dimensionality of the problem is also decreased significantly, which means ease of convergence and a smaller likelihood of suboptimal solutions. While our approach is conceptually straightforward, the dependencies get considerably more complex with increasing model size. To generate dependency definitions automatically, a web-accessible program is available at http://biomath.info/poolfit/constraints.

Ramakrishnan, Rajasekhar; Ramakrishnan, Janak D.

2008-01-01

184

Effects of experimental weight perturbation on skeletal muscle work efficiency, fuel utilization, and biochemistry in human subjects  

PubMed Central

Maintenance of a body weight 10% above or below that “customary” for lean or obese individuals results in respective increases or decreases in the energy expended in low levels of physical activity (nonresting energy expenditure, NREE). These changes are greater than can be accounted for by the altered body weight or composition and are due mainly to altered skeletal muscle work efficiency at low levels of power generation. We performed biochemical analysis of vastus lateralis muscle needle biopsy samples to determine whether maintenance of an altered body weight was associated with changes in skeletal muscle histomorphology. We found that the maintenance of a 10% reduced body weight was associated with significant declines in glycolytic (phosphofructokinase, PFK) enzyme activity and, in particular, in the ratio of glycolytic to oxidative (cytochrome c oxidase, COX) enzyme activity without significant changes in the activities of enzymes relevant to mitochondrial density, respiratory chain activity, or fuel transport; or in skeletal muscle fiber type or glycogen stores. The fractional change in the ratio of PFK/COX activity in subjects following weight loss was significantly correlated with changes in the systemic respiratory exchange ratio (RER) and measures of mechanical efficiency of skeletal muscle at low workloads (pedaling a bicycle to generate 10 or 25 W of power). Thus, predictable changes in systemic skeletal muscle biochemistry accompany the maintenance of an altered body weight and account for a significant portion of the variance in skeletal muscle work efficiency and fuel utilization at reduced body weight.

Goldsmith, Rochelle; Joanisse, Denis R.; Gallagher, Dympna; Pavlovich, Katherine; Shamoon, Elisabeth; Leibel, Rudolph L.

2010-01-01

185

Long-duration high-efficiency operation of a continuously pulsed copper laser utilizing copper bromide as a lasant  

NASA Technical Reports Server (NTRS)

A copper laser utilizing copper bromide as a lasant and neon as the buffer gas has been operated at an average laser power of between 16 and 19.5 W for a period of 68 h. Lasing was attained at a pulsing rate of 16.7 kHz in a quartz discharge tube 2.5-cm in diameter with an electrode separation of 200 cm. The laser energy/pulse and peak power/pulse corresponding to an average power of 19.5 W are 1.2 mJ and 30 kW, respectively. The ratio of laser power at 510.6 and 578.2 nm varied from 3.9 to 1.1 corresponding to a total average laser power of 4 and 18 W, respectively. The highest wall plug and capacitor efficiency measured during 68 h of operation were 0.7 and 1.1%, respectively.

Chen, C. J.; Bhanji, A. M.; Russell, G. R.

1978-01-01

186

Promoting emerging energy-efficiency technologies and practices by utilities in a restructured energy industry: A report from California  

SciTech Connect

The potential energy savings from emerging technologies (i.e., those technologies emerging from research and development) represent a significant resource to California and the US This paper describes how California's investor-owned utilities (IOUs) have been promoting emerging technologies over the last three years to increase energy efficiency in the buildings sector. During these years, the IOUs have experienced significant changes in their regulatory environment as part of the restructuring of the energy industry in California. These regulatory changes have impacted the way emerging technologies are treated by the regulatory community and the IOUs. After reviewing these changes, the paper concludes by discussing potential opportunities to improve the market penetration of emerging technologies.

Vine, Edward L.

2000-07-01

187

Energy-efficient reference gait generation utilizing variable ZMP and vertical hip motion based on inverted pendulum model for biped robots  

Microsoft Academic Search

Energy-efficient reference gait generation algorithm is suggested utilizing variable ZMP (Zero Moment Point) and vertical hip motion, which maxmizes the energy efficiency for cyclic gaits, based on inverted pendulum model (IPM) for biped robots. As observed in natural human walking, the robot's vertical hip motion (with average height and amplitude of hip ripple) as well as allowing variable ZMP pattern,

Hyeok Ki Shin; Byung Kook Kim

2010-01-01

188

Partitioning of heat production in growing pigs as a tool to improve the determination of efficiency of energy utilization  

PubMed Central

In growing pigs, the feed cost accounts for more than 60% of total production costs. The determination of efficiency of energy utilization through calorimetry measurements is of importance to sustain suitable feeding practice. The objective of this paper is to describe a methodology to correct daily heat production (HP) obtained from measurements in respiration chamber for the difference in energy expenditure related to physical activity between animals. The calculation is based on a preliminary published approach for partitioning HP between HP due to physical activity (AHP), thermic effect of feeding (TEF) and basal metabolic rate (fasting HP; FHP). Measurements with male growing pigs [mean body weight (BW): 115 kg] which were surgically castrated (SC), castrated through immunization against GnRH (IC), or kept as entire male (EM) were used as an example. Animals were fed the same diet ad-libitum and were housed individually in two 12-m3 open-circuit respiration chambers during 6 days when fed ad-libitum and one supplementary day when fasted. Physical activity was recorded through interruption of an infrared beam to detect standing and lying positions and with force transducers that recorded the mechanical force the animal exerted on the floor of the cage. Corrected AHP (AHPc), TEF (TEFc), and HP (HPc) were calculated to standardize the level of AHP between animals, assuming that the ratio between AHPc and ME intake should be constant. Inefficiency of energy utilization (sum of AHPc and TEFc) was lower than the inefficiency estimated from the slope of the classical relationship between HPc and ME intake but was associated with higher requirements for maintenance. Results indicate that EM pigs had higher FHP but lower TEFc than IC and SC pigs. These results agree with the higher contents in viscera of EM pigs that stimulate their basal metabolic rate and with the reduced utilization of dietary protein to provide energy for maintenance energy requirements and fat deposition (FD).

Labussiere, Etienne; Dubois, Serge; van Milgen, Jaap; Noblet, Jean

2013-01-01

189

Human cytoplasmic antiproteinase neutralizes rapidly and efficiently chymotrypsin and trypsin-like proteases utilizing distinct reactive site residues.  

PubMed

Human cytoplasmic antiproteinase (CAP) is an intracellular serpin that has been reported to utilize Arg341 as the reactive site P1 residue to neutralize a broad variety of extracellular serine proteases with trypsin-like specificity. Both native CAP and recombinant CAP purified from Escherichia coli were observed to form SDS-stable complexes not only with 125I-thrombin and 125I-urokinase, but also with 125I-chymotrypsin. Kinetic studies indicated that the amidolytic activity of chymotrypsin is inhibited efficiently and rapidly by CAP in a two-step process with a dissociation constant Ki of an initial loose complex of 3.3 nM, a forward isomerization rate constant k2 to the tight complex of 0.014 s-1, and an overall second order association rate constant of 6 x 10(6) M-1 s-1, similar to the kinetic constants obtained for the formation of the trypsin-CAP complex. N-terminal amino acid sequencing and mass spectrometry indicated that chymotrypsin interacts with CAP at Met340, in contrast to thrombin, which interacts as expected at Arg341. Thus, CAP is the first serpin that has been shown to be capable to inhibit efficiently and with similar association rate constants different proteases at distinct reactive site residues, strongly supporting the notion of a highly mobile and flexible serpin reactive site loop and suggesting that this inhibitor may have evolved separate reactive sites for the specific regulation of different proteolytic activities. PMID:8662739

Riewald, M; Schleef, R R

1996-06-14

190

Improved efficiency of bulk heterojunction hybrid solar cells by utilizing CdSe quantum dot-graphene nanocomposites.  

PubMed

We present a significant efficiency enhancement of hybrid bulk heterojunction solar cells by utilizing CdSe quantum dots attached to reduced graphene oxide (rGO) as the electron accepting phase, blended with the PCPDTBT polymer. The quantum dot attachment to rGO was achieved following a self-assembly approach, recently developed, using thiolated reduced graphene oxide (TrGO) to form a TrGO-CdSe nanocomposite. Therefore, we are able to obtain TrGO-CdSe quantum dot/PCPDTBT bulk-heterojunction hybrid solar cells with power conversion efficiencies of up to 4.2%, compared with up to 3% for CdSe quantum dot/PCPDTBT devices. The improvement is mainly due to an increase of the open-circuit voltage from 0.55 V to 0.72 V. We found evidence for a significant change in the heterojunction donor-acceptor blend nanomorphology, observable by a more vertical alignment of the TrGO-quantum dot nanocomposites in the z-direction and a different nanophase separation in the x-y direction compared to the quantum dot only containing device. Moreover, an improved charge extraction and trap state reduction were observed for TrGO containing hybrid solar cells. PMID:24820059

Eck, Michael; Pham, Chuyen Van; Züfle, Simon; Neukom, Martin; Sessler, Martin; Scheunemann, Dorothea; Erdem, Emre; Weber, Stefan; Borchert, Holger; Ruhstaller, Beat; Krüger, Michael

2014-05-28

191

Utilization of non-AUG initiation codons in a flow cytometric method for efficient selection of recombinant cell lines.  

PubMed

Here we describe a method that couples flow cytometric detection with the attenuated translation of a reporter protein to enable efficient selection of CHO clones producing high levels of recombinant proteins. In this system, a small cell surface reporter protein is expressed from an upstream open reading frame utilizing a non-AUG initiation (alternate start) codon. Due to the low translation initiation efficiency of this alternate start codon, the majority of translation initiation events occur at the first AUG of the downstream open reading frame encoding the recombinant protein of interest. While translation of the reporter is significantly reduced, the levels are sufficient for detection using flow cytometric methods and, in turn, predictive of protein expression from the gene of interest since both ORFs are translated from the same mRNA. Using this system, CHO cells have been sorted to obtain enriched pools producing significantly higher levels of recombinant proteins than the starting cell population and clones with significantly better productivity than those generated from limiting dilution cloning. This method also serves as an effective screening tool during clone expansion to enable resources to be focused solely on clones with both high and stable expression. PMID:21618473

Cairns, Victor R; DeMaria, Christine T; Poulin, Francis; Sancho, José; Liu, Ping; Zhang, Jin; Campos-Rivera, Juanita; Karey, Kenneth P; Estes, Scott

2011-11-01

192

High-Efficiency Phosphorescent White Organic Light-Emitting Diodes with Stable Emission Spectrum Based on RGB Separately Monochromatic Emission Layers  

NASA Astrophysics Data System (ADS)

Highly efficient phosphorescent white organic light-emitting diodes (WOLEDs) with stable emission spectra are successfully fabricated by using an RGB three-color separately monochromatic emission layer (EML) structure. The EML consists of a sequence of bis(2-methyldibenzo[f, h]quinoxaline) (acetylacetonate) iridium (III) (Ir(MDQ)2 (acac)) doped tris(4-carbazoyl-9-ylphenyl)amine (TCTA) as the red emission layer, iridium, tris(2-phenylpyidine)(Ir(ppy)3) doped TCTA as the green emission layer and iridium(III) [bis(4, 6-difuorophenyl)-pyridinato-N, C2']picolinate (FIrpic) doped a mixed-host of TCTA and tris(4-carbazoyl-9-ylphenyl)amine (26DCz PPy) as the blue emission layer. Without using any out-coupling techniques, the resulting WOLEDs achieve a power efficiency of 42lm/W at 100 cd/m2, and 34 lm/W at 1000 cd/m2. The WOLEDs also show excellent spectrum stability with bias voltages, remaining the Commission Internationale de L'Eclairage coordinates at (0.44, 0.43) from 1000 cd/m2 to 10000 cd/m2 and the color rendering index is as high as over 80. We contribute the stable emission spectrum to the RGB separate EML structure that successfully suppresses the undesired competition between host-guest energy transfer and direct exciton formation on emissive dopants by effectively controlling the position of exciton recombination region.

Zhang, Zhi-Qiang; Liu, Yi-Peng; Dai, Yan-Feng; Chen, Jiang-Shan; Ma, Dong-Ge; Zhang, Hong-Mei

2014-04-01

193

Highly efficient SO2 absorption/activation and subsequent utilization by polyethylene glycol-functionalized Lewis basic ionic liquids.  

PubMed

Up to now, flue-gas desulfurization (FGD) is one of the most effective techniques to control SO(2) emission from the combustion of fossil fuels. The conventional technology for FGD poses serious inherent drawbacks such as formation of byproducts and volatilization of solvents. In this work, polyethylene glycol (PEG)-functionalized Lewis basic ionic liquids (ILs) derived from DABCO were proved to be highly efficient absorbents for FGD due to its specific features such as high thermal stability, negligible vapor pressure, high loading capacity. Notably, PEG(150)MeDABCONTf(2) gave an extremely high SO(2) capacity (4.38 mol mol(-1) IL), even under 0.1 bar SO(2) partial pressure (1.01 mol mol(-1) IL), presumably owing to the strong SO(2)-philic characterization of the PEG chain. Furthermore, the absorbed SO(2) could be easy to release by just bubbling N(2) at room temperature, greatly reducing energy requirement for SO(2) desorption. In addition, SO(2)/CO(2) selectivity (110) of PEG(150)MeDABCONTf(2) is two times larger than the non-functionalized imidazolium IL (45). On the other hand, through activation of SO(2) with the tertiary nitrogen in the cation, Lewis basic ILs such as PEG(150)MeDABCOBr proved to be efficient catalysts for the conversion of SO(2) to some value-added chemicals such as cyclic sulfites without utilization of any organic solvent or additive. Thus, this protocol would pave the way for the development of technological innovation towards efficient and low energy demanded practical process for SO(2) absorption and subsequent transformation. PMID:23090138

Yang, Zhen-Zhen; He, Liang-Nian; Song, Qing-Wen; Chen, Kai-Hong; Liu, An-Hua; Liu, Xiang-Ming

2012-12-01

194

Call admission control policies in cellular wireless networks with spectrum renting  

Microsoft Academic Search

Radio spectrum is scarce and precious resource in wireless networks. To efficiently utilize radio spectrum, a wireless network can rent radio channels from another wireless network and returns back the rented channels when the rented channels are required to be withdrawn. The rental and withdrawal of radio channels result in two phenomena: (i) variable number of radio channels in a

Show-Shiow Tzeng

2009-01-01

195

A Novel Bargaining Based Dynamic Spectrum Management Scheme in Reconfigurable Systems  

Microsoft Academic Search

B3G wireless networks are expected to be characterized by the pouring of diversified services supported by different operators. In parallel with this, how to efficiently utilize the limited radio spectrum and guarantee the operator¿s profits has become a joint economical and technical problem. As a possible solution, in this paper, we set forth a novel bargaining approach for dynamic spectrum

Miao Pan; Shuo Liang; Haozhi Xiong; Jie Chen; Guangyi Liu

2006-01-01

196

Improved light extraction efficiency with angle independent electroluminescence spectrum in nano-phosphor coated white organic light emitting diodes  

Microsoft Academic Search

We have fabricated down converted white organic light emitting diodes (WOLEDs) by using cerium doped YAG nano-phosphor after mixing them in binder poly venyle acetate (PVAc) polymer matrix by changing the concentration of nano-phosphor. Down conversion layer was deposited by using a low cost spin coating technique. The enhancement in extraction efficiency by a factor of about 1.6 was found

Arunandan Kumar; Ritu Srivastava; Priyanka Tyagi; D. S. Mehta; M. N. Kamalasanan

2011-01-01

197

Technical Background Paper for Utility and Performance Relative to Consumer-Product Energy-Efficiency Standards (For Proposed Energy-Efficiency Standards).  

National Technical Information Service (NTIS)

This report summarizes an investigation of the relative utility and performance of nine major household consumer products covered by the Energy Policy and Conservation Act. The objective of the investigation was to define the terms utility and performance...

J. L. Coggins

1979-01-01

198

Device-centric spectrum management  

Microsoft Academic Search

Efficient spectrum allocation in open spectrum systems is a challenging problem, particularly for devices with constrained communication resources such as sensor and mobile ad hoc networks. We propose a device-centric spectrum management scheme with low communication costs, where users observe local interference patterns and act independently according to preset spectrum rules. We propose five rules that tradeoff performance with implementation

Haitao Zheng; Lili Cao

2005-01-01

199

Genome Sequence of Thermophilic Bacillus licheniformis Strain 3F-3, an Efficient Pentose-Utilizing Producer of 2,3-Butanediol  

PubMed Central

Bacillus licheniformis strain 3F-3 is an efficient pentose-utilizing producer of platform chemical, 2,3-butanediol. Here we present a 4.1-Mb assembly of its genome. The key genes for pentose utilization, regulation, and metabolism of 2,3-butanediol were annotated, which may provide further insights into the molecular mechanism of 2,3-butanediol production from biomass pentose.

Li, Lixiang; Wang, Yu; Wang, Kai; Li, Kun; Ma, Cuiqing

2014-01-01

200

Efficient immobilization of mushroom tyrosinase utilizing whole cells from Agaricus bisporus and its application for degradation of bisphenol A.  

PubMed

A simple and efficient procedure for preparation and immobilization of tyrosinase enzyme was developed utilizing whole cells from the edible mushroom Agaricus bisporus, without the need for enzyme purification. Tyrosinase activity in the cell preparation remained constant during storage at 21 °C for at least six months. The cells were entrapped in chitosan and alginate matrix capsules and characterized with respect to their resulting tyrosinase activity. A modification of the alginate with colloidal silica enhanced the activity due to retention of both cells and tyrosinase from fractured cells, which otherwise leached from matrix capsules. The observed activity was similar to the activity that was obtained with immobilized isolated tyrosinase in the same material. Mushroom cells in water were susceptible to rapid inactivation, whereas the immobilized cells maintained 73% of their initial activity after 30 days of storage in water. Application in repeated batch experiments resulted in almost 100% conversion of endocrine disrupting bisphenol A (BPA) for 11 days, under stirring conditions, and 50-60% conversion after 20 days, without stirring under continuous usage. The results represent the longest yet reported application of immobilized tyrosinase for degradation of BPA in environmental water samples. PMID:24727498

Kampmann, Markus; Boll, Stefan; Kossuch, Jan; Bielecki, Julia; Uhl, Stefan; Kleiner, Beatrice; Wichmann, Rolf

2014-06-15

201

Efficiency of Purine Utilization by Helicobacter pylori: Roles for Adenosine Deaminase and a NupC Homolog  

PubMed Central

The ability to synthesize and salvage purines is crucial for colonization by a variety of human bacterial pathogens. Helicobacter pylori colonizes the gastric epithelium of humans, yet its specific purine requirements are poorly understood, and the transport mechanisms underlying purine uptake remain unknown. Using a fully defined synthetic growth medium, we determined that H. pylori 26695 possesses a complete salvage pathway that allows for growth on any biological purine nucleobase or nucleoside with the exception of xanthosine. Doubling times in this medium varied between 7 and 14 hours depending on the purine source, with hypoxanthine, inosine and adenosine representing the purines utilized most efficiently for growth. The ability to grow on adenine or adenosine was studied using enzyme assays, revealing deamination of adenosine but not adenine by H. pylori 26695 cell lysates. Using mutant analysis we show that a strain lacking the gene encoding a NupC homolog (HP1180) was growth-retarded in a defined medium supplemented with certain purines. This strain was attenuated for uptake of radiolabeled adenosine, guanosine, and inosine, showing a role for this transporter in uptake of purine nucleosides. Deletion of the GMP biosynthesis gene guaA had no discernible effect on mouse stomach colonization, in contrast to findings in numerous bacterial pathogens. In this study we define a more comprehensive model for purine acquisition and salvage in H. pylori that includes purine uptake by a NupC homolog and catabolism of adenosine via adenosine deaminase.

Miller, Erica F.; Vaish, Soumya; Maier, Robert J.

2012-01-01

202

Spectrum management considerations of adaptive power control in satellite networks  

NASA Technical Reports Server (NTRS)

Adaptive power control concepts for the compensation of rain attenuation are considered for uplinks and downlinks. The performance of example power-controlled and fixed-EIRP uplinks is compared in terms of C/Ns and C/Is. Provisional conclusions are drawn with regard to the efficacy of uplink and downlink power control orbit/spectrum utilization efficiency.

Sawitz, P.; Sullivan, T.

1983-01-01

203

Spectrum management considerations of adaptive power control in satellite networks  

NASA Astrophysics Data System (ADS)

Adaptive power control concepts for the compensation of rain attenuation are considered for uplinks and downlinks. The performance of example power-controlled and fixed-EIRP uplinks is compared in terms of C/Ns and C/Is. Provisional conclusions are drawn with regard to the efficacy of uplink and downlink power control orbit/spectrum utilization efficiency.

Sawitz, P.; Sullivan, T.

204

Utility of NCCLS Guidelines for Identifying Extended-Spectrum -Lactamases in Non-Escherichia coli and Non-Klebsiella spp. of Enterobacteriaceae  

Microsoft Academic Search

NCCLS screening and confirmation methods for detecting extended-spectrum -lactamases (ESBLs) apply only to Escherichia coli and Klebsiella spp., yet ESBLs have been found in other members of the family Enterobacteriaceae. We evaluated the effectiveness of NCCLS methods for detecting ESBLs in 690 gram- negative isolates of Enterobacteriaceae that excluded E. coli, Klebsiella pneumoniae, and Klebsiella oxytoca. Isolates were collected between

Mitchell J. Schwaber; Patti M. Raney; J. Kamile Rasheed; James W. Biddle; Portia Williams; John E. McGowan; Fred C. Tenover

2004-01-01

205

Photosynthetic Light Utilization Efficiency, Photosystem II Heterogeneity, and Fluorescence Quenching in Chlamydomonas reinhardtii during the Induction of the CO2-Concentrating Mechanism 1  

PubMed Central

The photosynthetic light-response curve, the relative amounts of the different photosystem II (PSII) units, and fluorescence quenching were altered in an adaptive manner when CO2-enriched wild-type Chlamydomonas reinhardtii cells were transferred to low levels of CO2. This treatment is known to result in the induction of an energy-dependent CO2-concentrating mechanism (CCM) that increases the internal inorganic carbon concentration and thus the photosynthetic CO2 utilization efficiency. After 3 to 6 h of low inorganic carbon treatment, several changes in the photosynthetic energy-transducing reactions appeared and proceeded for about 12 h. After this time, the fluorescence parameter variable/maximal fluorescence yield and the amounts of both PSII? and PSII? (secondary quinone electron acceptor of PSII-reducing) centers had decreased, whereas the amount of PSII? (secondary quinone electron acceptor of PSII-nonreducing) centers had increased. The yield of noncyclic electron transport also decreased during the induction of the CCM, whereas both photochemical and nonphotochemical quenching of PSII fluorescence increased. Concurrent with these changes, the photosynthetic light-utilization efficiency also decreased significantly, largely attributed to a decline in the curvature parameter ?, the convexity of the photosynthetic light-response curve. Thus, it is concluded that the increased CO2 utilization efficiency in algal cells possessing the CCM is maintained at the cost of a reduced light utilization efficiency, most probably due to the reduced energy flow through PSII.

Falk, Stefan; Palmqvist, Kristin

1992-01-01

206

Reflection hologram solar spectrum-splitting filters  

NASA Astrophysics Data System (ADS)

In this paper we investigate the use of holographic filters in solar spectrum splitting applications. Photovoltaic (PV) systems utilizing spectrum splitting have higher theoretical conversion efficiency than single bandgap cell modules. Dichroic band-rejection filters have been used for spectrum splitting applications with some success however these filters are limited to spectral control at fixed reflection angles. Reflection holographic filters are fabricated by recording interference pattern of two coherent beams at arbitrary construction angles. This feature can be used to control the angles over which spectral selectivity is obtained. In addition focusing wavefronts can also be used to increase functionality in the filter. Holograms fabricated in dichromated gelatin (DCG) have the benefit of light weight, low scattering and absorption losses. In addition, reflection holograms recorded in the Lippmann configuration have been shown to produce strong chirping as a result of wet processing. Chirping broadens the filter rejection bandwidth both spectrally and angularly. It can be tuned to achieve spectral bandwidth suitable for spectrum splitting applications. We explore different DCG film fabrication and processing parameters to improve the optical performance of the filter. The diffraction efficiency bandwidth and scattering losses are optimized by changing the exposure energy, isopropanol dehydration bath temperature and hardening bath duration. A holographic spectrum-splitting PV module is proposed with Gallium Arsenide (GaAs) and silicon (Si) PV cells with efficiency of 25.1% and 19.7% respectively. The calculated conversion efficiency with a prototype hologram is 27.94% which is 93.94% compared to the ideal spectrum-splitting efficiency of 29.74%.

Zhang, Deming; Gordon, Michael; Russo, Juan M.; Vorndran, Shelby; Escarra, Matthew; Atwater, Harry; Kostuk, Raymond K.

207

Group-based spectrum assignment in dynamic flex-grid optical networks  

NASA Astrophysics Data System (ADS)

Traditional wavelength switched optical network employing wavelength-division-multiplexing (WDM) technology, allocates constant spectrum band to different kinds of services, which lacks flexibility in spectrum provisioning and thus reduces the resource utilization efficiency. Flex-grid technology, which introduces a finer spectrum granularity and allocates spectrum to different services flexibly according to their required bandwidth, is considered a promising candidate solution to improve the resource utilization efficiency of an optical network. However, since multiple contiguous spectrum granularities are usually assigned to a single service in such flex-grid optical network, the spectrum continuity and contiguity constraints should always be guaranteed, which may induce spectrum fragmentation. With the accumulation of spectrum fragmentation, available spectrum resources decrease, and this will greatly worsen the performance of the whole network, especially in networking. Therefore, spectrum fragmentation is considered a serious problem in flex-grid optical networks and many schemes have been proposed to solve it. These existing schemes, known as defragmentation, can reduce spectrum fragmentation either by rerouting the lightpath or by reallocating the spectrum for a service, which re-optimizes the spectrum resources. However, in the rerouting or reallocation procedure, existing traffic may be disrupted or extra resources, such as alternative spectrum or expensive spectrum convertors, are needed. None of these schemes can solve spectrum fragmentation with both no disrupted traffic and extra resources. It is because all these schemes utilize remedial methods to solve fragmentation problem and either disrupted traffic or extra resources are the cost when they cope with the defragmented spectrum. Different from all the above schemes, we propose a precautionary method to solve fragmentation problem in this paper. By introducing group-based spectrum assignment algorithm into flex-grid optical networks, spectrum resources are sorted into groups and each spectrum group only accommodates one specific kind of services. Since released spectrum can always be reused by the services of the same kind, spectrum fragmentation is prevented from its generation. Simulation results demonstrate that the proposed algorithm induces no spectrum fragmentations and is suitable to accommodate high-speed services.

Qiu, Yang

2013-10-01

208

Utility residential new construction programs: Going beyond the code. A report from the Database on Energy Efficiency Programs (DEEP) Project  

SciTech Connect

Based on an evaluation of 10 residential new construction programs, primarily sponsored by investor-owned utilities in the United States, we find that many of these programs are in dire straits and are in danger of being discontinued because current inclusion of only direct program effects leads to the conclusion that they are not cost-effective. We believe that the cost-effectiveness of residential new construction programs can be improved by: (1) promoting technologies and advanced building design practices that significantly exceed state and federal standards; (2) reducing program marketing costs and developing more effective marketing strategies; (3) recognizing the role of these programs in increasing compliance with existing state building codes; and (4) allowing utilities to obtain an ``energy-savings credit`` from utility regulators for program spillover (market transformation) impacts. Utilities can also leverage their resources in seizing these opportunities by forming strong and trusting partnerships with the building community and with local and state government.

Vine, E.

1995-08-01

209

Preliminary report on the photoionization efficiency spectrum, ionization energy and heat of formation of Br(sub 2)O; and the appearance energy of BrO(sup +) (Br(sub 2)O).  

National Technical Information Service (NTIS)

We report experimental results for the photoionization efficiency (PIE) spectrum of Br(sub 2)O along with the ionization energy (derived form the ionization threshold) and the appearance energy (AE) of BrO(sup +) (Br(sub 2)O). A value for the heat of form...

R. P. Thorn P. S. Monks L. J. Stief S. C. Kuo Z. Zhang

1995-01-01

210

Non-streaming high-efficiency perforated semiconductor neutron detectors, methods of making same and measuring wand and detector modules utilizing same  

DOEpatents

Non-streaming high-efficiency perforated semiconductor neutron detectors, method of making same and measuring wands and detector modules utilizing same are disclosed. The detectors have improved mechanical structure, flattened angular detector responses, and reduced leakage current. A plurality of such detectors can be assembled into imaging arrays, and can be used for neutron radiography, remote neutron sensing, cold neutron imaging, SNM monitoring, and various other applications.

McGregor, Douglas S. (Riley, KS); Shultis, John K. (Manhattan, KS); Rice, Blake B. (Manhattan, KS); McNeil, Walter J. (Winnfield, KS); Solomon, Clell J. (Wichita, KS); Patterson, Eric L. (Manhattan, KS); Bellinger, Steven L. (Manhattan, KS)

2010-12-21

211

Utilization of the bar gene to develop an efficient method for detection of the pollen-mediated gene flow in Chinese cabbage ( Brassica rapa spp. pekinensis )  

Microsoft Academic Search

To develop an efficient screening method for detection of the transgene in Chinese cabbage (Brassica rapa spp. pekinensis) utilizing Basta spray, optimal conditions for Basta application were examined in this study. Two transgenic Chinese cabbage\\u000a lines were obtained through Agrobacterium-mediated transformation and used as transgenic positive controls in the Basta screening experiment. Differential concentrations\\u000a of glufosinate-ammonium were sprayed into three

Chaewan Lim; Sunggil Kim; Yeonok Choi; Young-doo Park; Sung Uk Kim; Soon-Kee Sung

2007-01-01

212

A High Efficiency DC-DC Converter Topology Suitable for Distributed Large Commercial and Utility Scale PV Systems  

SciTech Connect

In this paper a DC-DC power converter for distributed photovoltaic plant architectures is presented. The proposed converter has the advantages of simplicity, high efficiency, and low cost. High efficiency is achieved by having a portion of the input PV power directly fed forward to the output without being processed by the converter. The operation of this converter also allows for a simplified maximum power point tracker design using fewer measurements

Mohammed S. Agamy; Maja Harfman-Todorovic; Ahmed Elasser; Robert L. Steigerwald; Juan A. Sabate; Song Chi; Adam J. McCann; Li Zhang; Frank Mueller

2012-09-01

213

Influence of condensed tannin on intake, digestibility, and efficiency of protein utilization in beef steers fed high concentrate diet  

Microsoft Academic Search

This trial was conducted to evaluate if the effect of condensed tannin (CT) is associated with a true protein source on intake, ruminal and total digestibility, ruminal digestion rate, protein efficiency, and microbial efficiency in beef steers fed high concentrate diet (87% of DM). Four Bos indicus steers (407±12kg of BW) fitted with rumen cannula were assigned to a 4×4

R. Mezzomo; P. V. R. Paulino; E. Detmann; S. C. Valadares Filho; M. F. Paulino; J. P. I. S. Monnerat; M. S. Duarte; L. H. P. Silva; L. S. Moura

2011-01-01

214

STUDY OF PCB DESTRUCTION EFFICIENCY AND PERFORMANCE FOR A COAL-FIRED UTILITY BOILER. VOLUME 1. TEST AND EVALUATION  

EPA Science Inventory

The report gives results of an evaluation of the adequacy of a large coal-fired utility boiler for disposal of oils containing 50-499 ppm of PCBs under conditions set by the PCB Disposal Regulations. TVA's Widows Creek Boiler No. 1 was used for the tests. In these tests, all effl...

215

The efficiency of utilization of metabolizable energy and apparent absorption of amino acids in sheep given spring- and autumn-harvested dried grass.  

PubMed

Three experiments were conducted with sheep given spring-harvested dried grass (SHG) and autumn-harvested dried grass (AHG). The first was a calorimetric trial to determine the metabolizable energy (ME) content of each grass and the efficiency with which sheep utilize their extra ME intakes above the maintenance level of intake. The second examined the relative amounts of extra non-ammonia-nitrogen (NAN) and individual amino acids absorbed from the small intestine per unit extra ME intake as the level of feeding was raised from energy equilibrium (M) to approximately 1.5 M. The third was a further calorimetric trial to investigate the effect of an abomasal infusion of 30 g casein/d on the efficiency of utilization of AHG. The ME content of the SHG (11.8 MJ/kg dry matter (DM] was higher than that of AHG (10.0 MJ/kg DM). The efficiency of utilization of ME for productive purposes (i.e. above the M level of intake; kf) was higher when given SHG (kf 0.54 between M and 2 M) than when given AHG (kf 0.43 between M and 2 M). As the level of intake of each grass was raised from M to 1.5 M there was a greater increment in the amounts of NAN (P less than 0.001) and the total amino acid (P less than 0.05) absorbed from the small intestines when sheep were given the SHG (NAN absorption, SHG 5.4 g/d, AHG 1.5 g/d, SED 0.54; total amino acid absorption SHG 31.5 g/d, AHG 14.3 g/d, SED 5.24). Infusion of 30 g casein/d per abomasum of sheep given AHG at M and 1.5 M levels of intake increased (P less than 0.05) the efficiency of utilization of the herbage from kf 0.45 to kf 0.57. Consideration is given to the possibility that the higher efficiency of utilization of ME in sheep given SHG may be related to the amounts of extra glucogenic amino acids absorbed from the small intestine which provide extra reducing equivalents (NADPH) and glycerol phosphate necessary for the conversion of acetate into fatty acids. PMID:4063304

Macrae, J C; Smith, J S; Dewey, P J; Brewer, A C; Brown, D S; Walker, A

1985-07-01

216

Lipopolysaccharide-induced reductions in food intake do not decrease the efficiency of lysine and threonine utilization for protein accretion in chickens.  

PubMed

Exposure of animals to infectious agents induces immune responses that result in reductions in food consumption and weight gain. The effect of these changes on amino acid requirements and utilization remains unclear. Three assays were conducted with young chicks with Escherichia coli lipopolysaccharide (LPS) used to stimulate the immune system. An initial study was conducted to evaluate the effects of LPS on animal performance. In a daily or alternate day injection regimen for 9 d, chicks were given intraperitoneal injections of sterile saline containing 0, 100 or 400 microgram LPS. Administration of 100 or 400 microgram LPS daily, or every other day, decreased both weight gain and food consumption. In two subsequent growth assays, chicks were fed graded levels of lysine or threonine and injected with either 0 or 400 microgram LPS every other day to evaluate the effect of LPS administration on the efficiency of amino acid utilization. At the three lowest amino acid doses, whole-body protein accretion was a linear function of supplemental lysine or threonine intake, and slopes of the accretion curves were not altered by LPS administration. The dietary lysine concentration required to maximize protein accretion was unaffected by LPS, but the absolute lysine intake required to maximize chick performance was lower in LPS-injected chicks than in saline-injected chicks. These results show that LPS administration reduces weight gain, food intake, efficiency of food utilization and the absolute quantity of lysine required to maximize these criteria. However, LPS administration does not affect the efficiency of amino acid utilization, nor does it affect the concentration of dietary lysine required to maximize performance. PMID:9772147

Webel, D M; Johnson, R W; Baker, D H

1998-10-01

217

Development of an Advanced Deshaling Technology to Improve the Energy Efficiency of Coal Handling, Processing, and Utilization Operations  

SciTech Connect

The concept of using a dry, density-based separator to achieve efficient, near-face rock removal, commonly referred to as deshaling, was evaluated in several applications across the U.S.. Varying amounts of high-density rock exist in most run-of-mine feed. In the central Appalachian coalfields, a rock content exceeding 50% in the feed to a preparation plant is commonplace due to high amounts of out-of-seam dilution made necessary by extracting coal from thin seams. In the western U.S, an increase in out-of-seam dilution and environmental regulations associated with combustion emissions have resulted in a need to clean low rank coals and dry cleaning may be the only option. A 5 ton/hr mobile deshaling unit incorporating a density-based, air-table technology commercially known as the FGX Separator has been evaluated at mine sites located within the states of Utah, Wyoming, Texas, West Virginia, Virginia, Pennsylvania and Kentucky. The FGX technology utilizes table riffling principles with air as the medium. Air enters through the table and creates a fluidized bed of particles comprised of mostly fine, high density particles. The high density particle bed lifts the low-density coal particles to the top of the bed. The low-density coal moves toward the front of the table due to mass action and the downward slope of the table. The high-density particles settle through the fluidized particle bed and, upon making contact with the table, moves toward the back of the table with the assistance of table vibration. As a result, the low-density coal particles exit the front of the table closest to the feed whereas the high-density, high-ash content particles leave on the side and front of the table located at the farthest from the feed entry. At each test site, the run-of-mine feed was either directly fed to the FGX unit or pre-screened to remove the majority of the -6mm material. The surface moisture of the feed must be maintained below 9%. Pre-screening is required when the surface moisture of the feed coal exceeds the maximum limit. However, the content of -6mm in the feed to the FGX separator should be maintained between 10% and 20% to ensure an adequate fluidized bed. A parametric evaluation was conducted using a 3-level experimental design at each test site to identify the optimum separation performance and parameter values. The test data was used to develop empirical expressions that describe the response variables (i.e., mass yield and product ash content) as a function of the operating parameter values. From this process, it was established that table frequency and longitudinal slope are the most critical factors in controlling both mass yield and clean coal ash while the cross table slope was the least significant. Fan blower frequency is a critical parameter that controls mass yield. Although the splitter positions between product and middling streams and the middling and tailing streams were held constant during the tests, a separate evaluation indicated that performance is sensitive to splitter position within certain lengths of the table and insensitive in others. For a Utah bituminous coal, the FGX separator provided clean coal ash contents that ranged from a low of 8.57% to a high of 12.48% from a feed coal containing around 17% ash. From the 29 tests involved in the statistically designed test program, the average clean coal ash content was 10.76% while the tailings ash content averaged around 72%. One of the best separation performances achieved an ash reduction from 17.36% to 10.67% while recovering 85.9% of the total feed mass, which equated to an ash rejection value of around 47%. The total sulfur content was typically decreased from 1.61% to 1.49%. These performances were quantified by blending the middlings stream with the clean coal product. At a second Utah site, coal sources from three different bituminous coal seams were treated by the FGX deshaling unit. Three parameter values were varied based on the results obtained from Site No. 1 to obtain the optimum results shown in Table E-1. Approximately 9 tests w

Rick Honaker; Gerald Luttrell

2007-09-30

218

A General Framework for Wireless Spectrum Auctions  

Microsoft Academic Search

We propose a real-time spectrum auction framework to distribute spectrum among a large number wireless users under interference constraints. Our approach achieves conflict-free spectrum allocations that maximize auction revenue and spectrum utilization. Our design includes a compact and yet highly expressive bidding language, various pricing models to control tradeoffs between revenue and fairness, and fast auction clearing algorithms to compute

Sorabh Gandhi; Chiranjeeb Buragohain; Lili Cao; Haitao Zheng; Subhash Suri

2007-01-01

219

Development of high-efficiency cost-effective, zinc--chlorine batteries for utility peak-shaving, 1976. Interim report  

Microsoft Academic Search

The two principal thrusts of this program were battery scale-up by a factor of twenty from earlier work and investigation of the economics of zinc--chlorine peak-shaving batteries located at utility substations. Development programs on cell performance, electrode research, and materials of construction were conducted in support of these objectives. A battery was designed, built, and tested which delivered 18 kWh

Symons

1978-01-01

220

Rationelle Energieverwendung im Krankenhaus. Fallstudie Katharinenhospital Stuttgart. (Efficient energy utilization in the hospital. Case study Katharinenhospital Stuttgart).  

National Technical Information Service (NTIS)

The research carried out at the Katharinen Hospital in Stuttgart in the scope of the project of the Federal Ministry of Research and Technology (BMFT) 'Energy efficiency in the hospital' had the objective to check the results and experiences determined by...

A. Kraner F. Kerschkamp H. Schneider L. Rouvel R. Mangelsdorf

1992-01-01

221

Efficient Utilization of Greenhouse Gases in a Gas-to-Liquids Process Combined with CO2/Steam-Mixed Reforming and Fe-Based Fischer-Tropsch Synthesis.  

PubMed

Two process models for carbon dioxide utilized gas-to-liquids (GTL) process (CUGP) mainly producing light olefins and Fischer-Tropsch (F-T) synthetic oils were developed by Aspen Plus software. Both models are mainly composed of a reforming unit, an F-T synthesis unit and a recycle unit, while the main difference is the feeding point of fresh CO2. In the reforming unit, CO2 reforming and steam reforming of methane are combined together to produce syngas in flexible composition. Meanwhile, CO2 hydrogenation is conducted via reverse water gas shift on the Fe-based catalysts in the F-T synthesis unit to produce hydrocarbons. After F-T synthesis, the unreacted syngas is recycled to F-T synthesis and reforming units to enhance process efficiency. From the simulation results, it was found that the carbon efficiencies of both CUGP options were successfully improved, and total CO2 emissions were significantly reduced, compared with the conventional GTL processes. The process efficiency was sensitive to recycle ratio and more recycle seemed to be beneficial for improving process efficiency and reducing CO2 emission. However, the process efficiency was rather insensitive to split ratio (recycle to reforming unit/total recycle), and the optimum split ratio was determined to be zero. PMID:24933030

Zhang, Chundong; Jun, Ki-Won; Ha, Kyoung-Su; Lee, Yun-Jo; Kang, Seok Chang

2014-07-15

222

How DRB-XCL burners and air heater upgrade reduced NO sub x and improved efficiency at a western utility  

SciTech Connect

The Neil Simpson Unit is a 220,000 lb/hr pulverized coal boiler that was designed to fire a local Wyoming subbituminous coal. During the late 1980s, the Wyoming Department of Air Quality imposed emission limits on the Black Hills Power and Light Co., Neil Simpson Station. The new limits required Black Hills power to control not only particulate and sulfur dioxide (SO{sub 2}) emissions, but also nitrogen oxide (NO{sub x}) emissions. At the same time, Black Hills Power initiated an efficiency improvement study at Neil Simpson Station to investigate methods for reducing net electrical generation costs. This paper addresses the plant efficiency and emissions studies, startup activities, the operating problems and successful operating solutions for NO{sub x} control when firing a Wyoming subbituminous coal. Also included is a summary of the post-0retrofit boiler performance data.

Becker, W. (Babcock and Wilcox Co., Barberton, OH (US)); Stalcup, T.; Schild, V. (Black Hills Power and Light Co., Neil Simpson Station, Gillette, WY (US)); Kowalski, E. (Stone and Webster Engineering Corp., Denver, CO (US))

1992-01-01

223

Hybrid organic-inorganic heterojunction solar cells with 12% efficiency by utilizing flexible film-silicon with a hierarchical surface.  

PubMed

This paper reports an organic-inorganic hybrid solar cell with a hierarchical surface composed of high density silicon nanoholes and micro-desert textures. High-efficiency organic-inorganic hybrid solar cell Si/PEDOT-PSS with a hierarchical surface, showing a power conversion efficiency of 12%. The structure provides excellent light absorption over 97% for the spectral range of 300 to 1100 nm with a thickness of 60 ?m due to internal multiple reflections caused by subwavelength features of high density silicon nanoholes and micro-desert textures. In addition, from the angle of incidence (AOI) observed, even at the large angle of 75°, the reflectance value still exhibits less than 1%. With the advantage of very thin silicon material and inexpensive processing, hybrid silicon/polymer solar cells are promising for various applications and thus could be an economically feasible alternative energy solution in the future. PMID:24522339

Thiyagu, Subramani; Hsueh, Chen-Chih; Liu, Chien-Ting; Syu, Hong-Jhang; Lin, Tzu-Ching; Lin, Ching-Fuh

2014-03-21

224

An efficient 1H\\/ 31P double-resonance solid-state NMR probe that utilizes a scroll coil  

Microsoft Academic Search

The construction and performance of a scroll coil double-resonance probe for solid-state NMR on stationary samples is described. The advantages of the scroll coil at the high resonance frequencies of 1H and 31P include: high efficiency, minimal perturbations of tuning by a wide range of samples, minimal RF sample heating of high dielectric samples of biopolymers in aqueous solution, and

Christopher V. Grant; Siu-Ling Sit; Anna A. De Angelis; Kelli S. Khuong; Chin H. Wu; Leigh A. Plesniak

2007-01-01

225

Evaluation of higher distribution and/or utilization voltages. Third interim report (October 1979): analysis of individual component cost and/or energy efficiencies  

SciTech Connect

This interim report provides documentation on the third task, Analysis of Individual Component Cost and/or Energy Efficiencies, of DOE Contract No. ET-78-C-01-2866, Evaluation of Higher Distribution and/or Utilization Voltages. The work performed under this task includes the development of both cost and energy loss models for the distribution and customer utilization system elements as well as the analysis of critical performance variables for the types of motors in end use elements, as a function of voltage level. The purpose of this task is to provide individual component cost and energy models which will be incorporated in the global system optimization program under Task 4. A major output of this task is a mathematical model for each component's cost and/or energy losses and a graphical representation of each model.

Not Available

1981-04-01

226

Auction-Based Spectrum Sharing  

Microsoft Academic Search

We study auction mechanisms for sharing spectrum among a group of users, subject to a constraint on the interference temperature at a measurement point. The users access the channel using spread spectrum signaling and so interfere with each other. Each user receives a utility that is a function of the received signal-to-interference plus noise ratio. We p ropose two auction

Jianwei Huang; Randall A. Berry; Michael L. Honig

2006-01-01

227

Multiplex ligation-dependent probe amplification for genetic screening in autism spectrum disorders: Efficient identification of known microduplications and identification of a novel microduplication in ASMT  

PubMed Central

Background It has previously been shown that specific microdeletions and microduplications, many of which also associated with cognitive impairment (CI), can present with autism spectrum disorders (ASDs). Multiplex ligation-dependent probe amplification (MLPA) represents an efficient method to screen for such recurrent microdeletions and microduplications. Methods In the current study, a total of 279 unrelated subjects ascertained for ASDs were screened for genomic disorders associated with CI using MLPA. Fluorescence in situ hybridization (FISH), quantitative polymerase chain reaction (Q-PCR) and/or direct DNA sequencing were used to validate potential microdeletions and microduplications. Methylation-sensitive MLPA was used to characterize individuals with duplications in the Prader-Willi/Angelman (PWA) region. Results MLPA showed two subjects with typical ASD-associated interstitial duplications of the 15q11-q13 PWA region of maternal origin. Two additional subjects showed smaller, de novo duplications of the PWA region that had not been previously characterized. Genes in these two novel duplications include GABRB3 and ATP10A in one case, and MKRN3, MAGEL2 and NDN in the other. In addition, two subjects showed duplications of the 22q11/DiGeorge syndrome region. One individual was found to carry a 12 kb deletion in one copy of the ASPA gene on 17p13, which when mutated in both alleles leads to Canavan disease. Two subjects showed partial duplication of the TM4SF2 gene on Xp11.4, previously implicated in X-linked non-specific mental retardation, but in our subsequent analyses such variants were also found in controls. A partial duplication in the ASMT gene, located in the pseudoautosomal region 1 (PAR1) of the sex chromosomes and previously suggested to be involved in ASD susceptibility, was observed in 6–7% of the cases but in only 2% of controls (P = 0.003). Conclusion MLPA proves to be an efficient method to screen for chromosomal abnormalities. We identified duplications in 15q11-q13 and in 22q11, including new de novo small duplications, as likely contributing to ASD in the current sample by increasing liability and/or exacerbating symptoms. Our data indicate that duplications in TM4SF2 are not associated with the phenotype given their presence in controls. The results in PAR1/PAR2 are the first large-scale studies of gene dosage in these regions, and the findings at the ASMT locus indicate that further studies of the duplication of the ASMT gene are needed in order to gain insight into its potential involvement in ASD. Our studies also identify some limitations of MLPA, where single base changes in probe binding sequences alter results. In summary, our studies indicate that MLPA, with a focus on accepted medical genetic conditions, may be an inexpensive method for detection of microdeletions and microduplications in ASD patients for purposes of genetic counselling if MLPA-identified deletions are validated by additional methods.

Cai, Guiqing; Edelmann, Lisa; Goldsmith, Juliet E; Cohen, Ninette; Nakamine, Alisa; Reichert, Jennifer G; Hoffman, Ellen J; Zurawiecki, Danielle M; Silverman, Jeremy M; Hollander, Eric; Soorya, Latha; Anagnostou, Evdokia; Betancur, Catalina; Buxbaum, Joseph D

2008-01-01

228

Variation in the apparent sensitivity of the insulin-mediated inhibition of proteolysis to amino acid supply determines the efficiency of protein utilization.  

PubMed

1. The variability between normal individuals in the efficiency of postprandial protein utilization (PPU), a determinant of the apparent protein requirement, was examined in relation to the relative responses of protein synthesis and proteolysis to protein feeding by means of [1-13C]leucine turnover and balance studies.2. Twenty-five healthy adults were infused intravenously with L-[1-13C]leucine continuously for 9 h. This was started in the postabsorptive state (PA, 3 h) and followed by low-protein feeding (LP, 3 h), and then by isoenergetic high-protein feeding (HP, 3 h). This allowed protein intake to be varied against a constant postprandial insulin level so that the extent of any amino-acid-mediated responses which were additional to those exerted by insulin could be investigated. Leucine oxidation, O, and balance (intake-oxidation), protein synthesis, S, and degradation, D, were calculated from plasma [1-13C]alpha-ketoisocaproic acid enrichment and 13CO2 excretion.3.PPUprotein, calculated as change in leucine balance/change in intake (HP-LP), varied from 0.58 to 0.99 (mean=0. 81+/-0.10), independently of age or sex. PPUprotein varied directly with the inhibition of D and inversely with the increase in leucine concentration and stimulation of O and S.4. Efficient PPU, as demonstrated by the top quintile of individuals categorized in terms of PPUprotein, involves maximal inhibition of D by protein feeding with minimal increases in free amino acid concentrations, O and S. Lesser inhibition of D and greater stimulation of S and O characterized the lower, less efficient quintile. This indicates that the efficiency of protein utilization in individuals, and a component of their apparent protein requirement, is determined by the sensitivity of the insulin-mediated inhibition of proteolysis to amino acid supply. PMID:9831698

Fereday, A; Gibson, N R; Cox, M; Pacy, P J; Millward, D J

1998-12-01

229

High efficiency, quasi-instantaneous steam expansion device utilizing fossil or nuclear fuel as the heat source  

SciTech Connect

Thermal-hydraulic analysis of a specially designed steam expansion device (heat cavity) was performed to prove the feasibility of steam expansions at elevated rates for power generation with higher efficiency. The steam expansion process inside the heat cavity greatly depends on the gap within which the steam expands and accelerates. This system can be seen as a miniaturized boiler integrated inside the expander where steam (or the proper fluid) is generated almost instantaneously prior to its expansion in the work-producing unit. Relatively cold water is pulsed inside the heat cavity, where the heat transferred causes the water to flash to steam, thereby increasing its specific volume by a large factor. The gap inside the heat cavity forms a special nozzle-shaped system in which the fluid expands rapidly, accelerating toward the system outlet. The expansion phenomenon is the cause of ever-increasing fluid speed inside the cavity system, eliminating the need for moving parts (pumps, valves, etc.). In fact, the subsequent velocity induced by the sudden fluid expansion causes turbulent conditions, forcing accelerating Reynolds and Nusselt numbers which, in turn, increase the convective heat transfer coefficient. When the combustion of fossil fuels constitutes the heat source, the heat cavity concept can be applied directly inside the stator of conventional turbines, thereby greatly increasing the overall system efficiency.

Claudio Filippone, Ph.D.

1999-06-01

230

An efficient 1H/ 31P double-resonance solid-state NMR probe that utilizes a scroll coil  

NASA Astrophysics Data System (ADS)

The construction and performance of a scroll coil double-resonance probe for solid-state NMR on stationary samples is described. The advantages of the scroll coil at the high resonance frequencies of 1H and 31P include: high efficiency, minimal perturbations of tuning by a wide range of samples, minimal RF sample heating of high dielectric samples of biopolymers in aqueous solution, and excellent RF homogeneity. The incorporation of a cable tie cinch for mechanical stability of the scroll coil is described. Experimental results obtained on a Hunter Killer Peptide 1 (HKP1) interacting with phospholipid bilayers of varying lipid composition demonstrate the capabilities of this probe on lossy aqueous samples.

Grant, Christopher V.; Sit, Siu-Ling; De Angelis, Anna A.; Khuong, Kelli S.; Wu, Chin H.; Plesniak, Leigh A.; Opella, Stanley J.

2007-10-01

231

Utility of adsorbents in the purification of drinking water: a review of characterization, efficiency and safety evaluation of various adsorbents.  

PubMed

Clean drinking water is one of the implicit requisites fora healthy human population. However the growing industrialization and extensive use of chemicals for various concerns, has increased the burden of unwanted pollutants in the drinking water of developing countries like India. The entry of potentially hazardous substances into the biota has been magnifying day by day. In the absence of a possible stoppage of these, otherwise, useful chemicals, the only way to maintain safer water bodies is to develop efficient purifying technologies. One such immensely beneficial procedure that has been in use is that of purification of water using 'adsorbents'. Indigenous minerals and natural plants products have potential for removing many pollutants viz. fluoride, arsenic, nitrate, heavy metals, pesticides as well as trihalomethanes. Adsorbents which are derived from carbon, alumina, zeolite, clay minerals, iron ores, industrial by products, and natural products viz. parts of the plants, herbs and algal biomass offer promising potential of removal. In the recent years attention has been paid to develop process involving screening/pretreatment/activation/impregnation using alkalies, acids, alum, lime, manganese dioxide, ferric chloride and other chemicals which are found to enhance their adsorbing efficiency. Chemical characterization of these adsorbents recapitulates the mechanism of the process. It is imperative to observe that capacities of the adsorbents may vary depending on the characteristics, chemical modifications and concentration of the individual adsorbent. Removal kinetics is found to be based on the experimental conditions viz. pH, concentration of the adsorbate, quantity of the adsorbent and temperature. It is suggested that isotherm model is suitable tool to assess the adsorption capacities in batch and column modes. Safety evaluation and risk assessment of the process/products may be useful to provide guidelines for its sustainable disposal. PMID:20120453

Dubey, Shashi Prabha; Gopal, Krishna; Bersillon, J L

2009-05-01

232

Myocardial blood flow and its transit time, oxygen utilization, and efficiency of highly endurance-trained human heart.  

PubMed

Highly endurance-trained athlete's heart represents the most extreme form of cardiac adaptation to physical stress, but its circulatory alterations remain obscure. In the present study, myocardial blood flow (MBF), blood mean transit time (MTT), oxygen extraction fraction (OEF) and consumption (MVO2), and efficiency of cardiac work were quantified in highly trained male endurance athletes and control subjects at rest and during supine cycling exercise using [(15)O]-labeled radiotracers and positron emission tomography. Heart rate and MBF were lower in athletes both at rest and during exercise. OEF increased in response to exercise in both groups, but was higher in athletes (70 ± 21 vs. 63 ± 11 % at rest and 86 ± 13 vs. 73 ± 10 % during exercise). MTT was longer and vascular resistance higher in athletes both at rest and during exercise, but arterial content of 2,3-diphosphoglycerate (oxygen affinity) was unchanged. MVO2 per gram of myocardium trended (p = 0.08) lower in athletes both at rest and during exercise, while myocardial efficiency of work and MVO2 per beat were not different between groups. Arterial levels of free fatty acids were ~twofold higher in athletes likely leading to higher myocardial fatty acid oxidation and hence oxygen cost, which may have blunted the bradycardia-induced decrease in MVO2. Finally, the observed group differences in MBF, OEF, MTT and vascular resistance remained significant also after they were controlled for differences in MVO2. In conclusion, in highly endurance-trained human heart, increased myocardial blood transition time enables higher oxygen extraction levels with a lower myocardial blood flow and higher vascular resistance. These physiological adaptations to exercise training occur independently of the level of oxygen consumption and together with training-induced bradycardia may serve as mechanisms to increase functional reserve of the human heart. PMID:24866583

Heinonen, Ilkka; Kudomi, Nobuyuki; Kemppainen, Jukka; Kiviniemi, Antti; Noponen, Tommi; Luotolahti, Matti; Luoto, Pauliina; Oikonen, Vesa; Sipilä, Hannu T; Kopra, Jaakko; Mononen, Ilkka; Duncker, Dirk J; Knuuti, Juhani; Kalliokoski, Kari K

2014-07-01

233

Highly efficient colorimetric detection of target cancer cells utilizing superior catalytic activity of graphene oxide-magnetic-platinum nanohybrids.  

PubMed

Enzyme-linked immunosorbent assays (ELISAs) have most widely been applied in immunoassays for several decades. However, several unavoidable limitations (e.g., instability caused by structural unfolding) of natural enzymes have hindered their widespread applications. Here, we describe a new nanohybrid consisting of Fe?O? magnetic nanoparticles (MNPs) and platinum nanoparticles (Pt NPs), simultaneously immobilized on the surface of graphene oxide (GO). By synergistically integrating highly catalytically active Pt NPs and MNPs on GO whose frameworks possess high substrate affinity, the nanohybrid is able to achieve up to a 30-fold higher maximal reaction velocity (V(max)) compared to that of free GO for the colorimetric reaction of the peroxidase substrate, 3,3',5,5'-tetramethylbenzidine (TMB), and enable rapid detection of target cancer cells. Specifically, using this new assay system, clinically important breast cancer cells are detected in a 5 min time period at room temperature with high specificity and sensitivity. The remarkably high capability to catalyze oxidation reactions could allow the nanohybrid to replace conventional peroxidase-based immunoassay systems as part of new, rapid, robust and convenient assay systems which can be widely utilized for the identification of important target molecules. PMID:24322602

Kim, Moon Il; Kim, Min Su; Woo, Min-Ah; Ye, Youngjin; Kang, Kyoung Suk; Lee, Jinwoo; Park, Hyun Gyu

2014-01-16

234

ADAPTIVE FULL-SPECTRUM SOLAR ENERGY SYSTEMS CROSS-CUTTING R&D ON ADAPTIVE FULL SPECTRUM SOLAR ENERGY SYSTEMS FOR MORE EFFICIENT AND AFFORDABLE USE OF SOLAR ENERGY IN BUILDINGS AND HYBRID PHOTOBIOREACTORS  

SciTech Connect

This RD&D project is a three year team effort to develop a hybrid solar lighting (HSL) system that transports day light from a paraboloidal dish concentrator to a luminaire via a large core polymer fiber optic. The luminaire can be a device to distribute sunlight into a space for the production of algae or it can be a device that is a combination of day lighting and fluorescent lighting for office lighting. In this project, the sunlight is collected using a one-meter paraboloidal concentrator dish with two-axis tracking. The secondary mirror consists of eight planar-segmented mirrors that direct the visible part of the spectrum to eight fibers (receiver) and subsequently to eight luminaires. This results in about 8,200 lumens incident at each fiber tip. Each fiber can illuminate about 16.7 m{sup 2} (180 ft{sup 2}) of office space. The IR spectrum is directed to a thermophotovoltaic array to produce electricity. This report emphasizes the design of the thermophotovoltaic receiver and the whole system simulation model.

Byard D. Wood; Jeff D. Muhs

2003-10-01

235

ADAPTIVE FULL-SPECTRUM SOLAR ENERGY SYSTEMS CROSS-CUTTING R&D ON ADAPTIVE FULL-SPECTRUM SOLAR ENERGY SYSTEMS FOR MORE EFFICIENT AND AFFORDABLE USE OF SOLAR ENERGY IN BUILDINGS AND HYBRID PHOTOBIOREACTORS  

SciTech Connect

This RD&D project is a three year team effort to develop a hybrid solar lighting (HSL) system that transports day light from a paraboloidal dish concentrator to a luminaire via a large core polymer fiber optic. The luminaire can be a device to distribute sunlight into a space for the production of algae or it can be a device that is a combination of day lighting and fluorescent lighting for office lighting. In this project, the sunlight is collected using a one-meter paraboloidal concentrator dish with two-axis tracking. The secondary mirror consists of eight planar-segmented mirrors that direct the visible part of the spectrum to eight fibers (receiver) and subsequently to eight luminaires. This results in about 8,200 lumens incident at each fiber tip. Each fiber can illuminate about 16.7 m{sup 2} (180 ft{sup 2}) of office space. The IR spectrum is directed to a thermophotovoltaic array to produce electricity. This report describes several investigations of various aspects of the system. Taken as a whole, they confirm significant progress towards the technical feasibility of this technology.

Byard D. Wood; Jeff D. Muhs

2003-01-01

236

The Storage Spectrum  

NSDL National Science Digital Library

Virtually every modern computer system incorporates several different storage technologies to process data efficiently. A gentle introduction to data storage is given on this site, part of Red Hat, Inc.'s Linux System Administration Primer. The topics covered include: "The Storage Spectrum," "CPU Registers," "Cache Memory," "Cache Levels," "Main Memory - RAM," "Hard Drives," and "Off-Line Backup Storage."

2008-02-15

237

Spectrum Analyzers.  

National Technical Information Service (NTIS)

The report consists of a discussion of various kinds of Spectrum Analyzers used in electronics and of a compilation of the electrical characteristics of commercial and nomenclatured instruments. The commercial instrument characteristics are based upon cat...

J. Lustig

1971-01-01

238

Utilization of the graded universal testing system to increase the efficiency for assessing aerobic and anaerobic capacity  

NASA Technical Reports Server (NTRS)

The in-flight exercise test performed by cosmonauts as part of the Russian Exercise Countermeasure Program is limited to 5 minutes due to communication restrictions. During a recent graded exercise test on a U.S. Shuttle flight, the test was terminated early due to an upcoming loss of signal (LOS) with the ground. This exercise test was a traditional test where the subject's exercise capacity dictates the length of the test. For example, one crew member may take 15 minutes to complete the test, while another may take 18 minutes. The traditional exercise test limits the flight schedulers to large blocks of space flight time in order to provide medical and research personnel information on the fitness capacity (maximal oxygen uptake: VO2max) of crew members during flight. A graded exercise test that would take a finite amount of time and a set preparation and recovery time would ease this problem by allowing flight schedulers to plan exercise tests in advance of LOS. The Graded Universal Testing System (GUTS) was designed to meet this goal. Fitness testing of astronauts before and after flight provides pertinent data on many variables. The Detailed Supplemental Objective (DSO608) protocol (6) is one of the graded exercise tests (GXT) currently used in astronaut testing before and after flight. Test times for this protocol have lasted from 11 to 18 minutes. Anaerobic capacity is an important variable that is currently not being evaluated before and after flight. Recent reports (1,2,5) from the literature have suggested that the oxygen deficit at supramaximal exercise is a measure of anaerobic capacity. We postulated that the oxygen deficit at maximal exercise would be an indication of anaerobic capacity. If this postulate can be accepted, then the efficiency of acquiring data from a graded exercise test would increase at least twofold. To examine this hypothesis anaerobic capacity was measured using a modified treadmill test (3,4) designed to exhaust the anaerobic systems in approximately 45 to 75 seconds. Lactate concentration in the blood was analyzed after all tests, since lactate is the end-product of anaerobic energy production. Therefore, the peak lactate response is an additional indication of anaerobic capacity. A preliminary comparison of the GUTS and the DSO608 suggests that the GUTS protocol would increase the efficiency of VO2max testing of astronauts before and after flight. Results for anaerobic capacity have not been tabulated.

Rodgers, Sandra L.

1992-01-01

239

Module greenhouse with high efficiency of transformation of solar energy, utilizing active and passive glass optical rasters  

SciTech Connect

Since the eighties of the 20th century, various types of linear glass rasters for architectural usage have been developed in the Czech Republic made by the continuous melting technology. The development was focused on two main groups of rasters - active rasters with linear Fresnel lenses in fixed installation and with movable photo-thermal and/or photo-thermal/photo-voltaic absorbers. The second group are passive rasters based on total reflection of rays on an optical prism. During the last years we have been working on their standardization, exact measuring of their optical and thermal-technical characteristics and on creation of a final product that could be applied in solar architecture. With the project supported by the Ministry of Environment of the Czech Republic we were able to build an experimental greenhouse using these active and passive optical glass rasters. The project followed the growing number of technical objectives. The concept of the greenhouse consisted of interdependence construction - structural design of the greenhouse with its technological equipment securing the required temperature and humidity conditions in the interior of the greenhouse. This article aims to show the merits of the proposed scheme and presents the results of the mathematical model in the TRNSYS environment through which we could predict the future energy balance carried out similar works, thus optimizing the investment and operating costs. In this article description of various technology applications for passive and active utilization of solar radiation is presented, as well as some results of short-term and long-term experiments, including evaluation of 1-year operation of the greenhouse from the energy and interior temperature viewpoints. A comparison of the calculated energy flows in the greenhouse to real measured values, for verification of the installed model is also involved. (author)

Korecko, J.; Jirka, V. [ENKI, o.p.s., Dukelska 145, 379 01 Trebon (Czech Republic); Sourek, B. [ENKI, o.p.s., Dukelska 145, 379 01 Trebon (Czech Republic); Czech Technical University of Prague, Technicka 4, 166 07 Prague (Czech Republic); Cerveny, J. [ENKI, o.p.s., Dukelska 145, 379 01 Trebon (Czech Republic); Institute of Physical Biology, Zamek 136, 373 33 Nove Hrady (Czech Republic)

2010-10-15

240

Spectrum-splitting photovoltaic system using transmission holographic lenses  

NASA Astrophysics Data System (ADS)

The optical efficiency of a holographic spectrum-splitting optical system with transmission holographic lenses is investigated. Spectrum-splitting is a promising approach to improve the efficiency of photovoltaic (PV) systems. By removing the lattice-matching constraints, it is possible to utilize low-cost thin-film PV materials and fabrication techniques. Transmission holograms are fabricated with the recording of the interference patterns of two or more coherent beams. It is also possible to use converging construction wavefronts to record holographic gratings that are matched to the focusing beam from the primary concentrator optics. Experimental holograms are fabricated in dichromated gelatin, and high diffraction efficiency is obtained. A single holographic lens is used to divide a broad spectrum into two types of PV cells. The position and orientation of the PV cells are chosen to match the dispersion properties of the holographic lens. The optical transfer efficiency of the holographic lens is measured to be ˜90% at the peak with fast transitions between the high diffraction efficiency and the high transmission spectral regions. With a GaAs solar cell and a 2.1-eV bandgap solar cell, the system efficiency is 31.0% under one-sun which is improved by 11.9% over the best single PV cell. The achievable system efficiency with the prototype filter is 96% compared to that of the ideal system.

Zhang, Deming; Gordon, Michael; Russo, Juan M.; Vorndran, Shelby; Kostuk, Raymond K.

2013-01-01

241

Efficient targeting of adenoviral vectors to integrin positive vascular cells utilizing a CAR-cyclic RGD linker protein.  

PubMed

Vascular smooth muscle (VSMC) and endothelial cells (EC) are particularly resistant to infection by type 5 adenovirus (Ad) vectors. To overcome this limitation and target Ad vectors to ubiquitously expressed alpha(V)beta(3/5) integrins, we have generated a linker protein consisting of the extracellular domain of the coxsackie adenovirus receptor (CAR) connected via avidin to a biotinylated cyclic (c) RGD peptide. After optimization of CAR to cRGD and to Ad coupling, infection of mouse heart endothelial cells (H5V) could be augmented significantly, as demonstrated by 600-fold increased transgene expression levels. In EOMAs, a hemangioendothelioma-derived cell line, the fraction of infected cells was enhanced 4- to 6-fold. Furthermore, the fraction of infected primary mouse VSMC was increased from virtually 0% to 25%. Finally, in human umbilical vein endothelial cells, the number of GFP positive cells was enhanced from 2% to 75%. In conclusion, CAR-cRGD is a versatile and highly efficient construct to target Ad vectors to both transformed and primary VSMC and EC. PMID:16259946

Krom, Y D; Gras, J C E; Frants, R R; Havekes, L M; van Berkel, T J; Biessen, E A L; van Dijk, K Willems

2005-12-16

242

Hijack it, change it: how do plant viruses utilize the host secretory pathway for efficient viral replication and spread?  

PubMed Central

The secretory pathway of eukaryotic cells has an elaborated set of endomembrane compartments involved in the synthesis, modification, and sorting of proteins and lipids. The secretory pathway in plant cells shares many features with that in other eukaryotic cells but also has distinct characteristics important for fundamental cell and developmental processes and for proper immune responses. Recently, there has been evidence that the remodeling of this pathway, and often the formation of viral-induced organelles, play an important role in viral replication and spread. The modification of the host secretory pathway seems to be a common feature among most single-stranded positive ss(+)RNA and even some DNA viruses. In this review, we will present the recent advances in the understanding of the organization and dynamics of the plant secretory pathway and the molecular regulation of membrane trafficking in the pathway. We will also discuss how different plant viruses may interact with the host secretory pathway for their efficient replication and spread, with a focus on tobacco mosaic virus and turnip mosaic virus.

Patarroyo, Camilo; Laliberte, Jean-Francois; Zheng, Huanquan

2013-01-01

243

Hijack it, change it: how do plant viruses utilize the host secretory pathway for efficient viral replication and spread?  

PubMed

The secretory pathway of eukaryotic cells has an elaborated set of endomembrane compartments involved in the synthesis, modification, and sorting of proteins and lipids. The secretory pathway in plant cells shares many features with that in other eukaryotic cells but also has distinct characteristics important for fundamental cell and developmental processes and for proper immune responses. Recently, there has been evidence that the remodeling of this pathway, and often the formation of viral-induced organelles, play an important role in viral replication and spread. The modification of the host secretory pathway seems to be a common feature among most single-stranded positive ss(+)RNA and even some DNA viruses. In this review, we will present the recent advances in the understanding of the organization and dynamics of the plant secretory pathway and the molecular regulation of membrane trafficking in the pathway. We will also discuss how different plant viruses may interact with the host secretory pathway for their efficient replication and spread, with a focus on tobacco mosaic virus and turnip mosaic virus. PMID:23335933

Patarroyo, Camilo; Laliberté, Jean-François; Zheng, Huanquan

2012-01-01

244

ADAPTIVE FULL-SPECTRUM SOLAR ENERGY SYSTEMS Cross-Cutting R & D on adaptive full-spectrum solar energy systems for more efficient and affordable use of solar energy in buildings and hybrid photobioreactors  

SciTech Connect

This RD&D project is a three year team effort to develop a hybrid solar lighting (HSL) system that transports daylight from a paraboloidal dish concentrator to a luminaire via a bundle of polymer fiber optics. The luminaire can be a device to distribute sunlight into a space for the production of algae or it can be a device that is a combination of daylighting and electric lighting for space/task lighting. In this project, the sunlight is collected using a one-meter paraboloidal concentrator dish with two-axis tracking. For the third generation (beta) system, the secondary mirror is an ellipsoidal mirror that directs the visible light into a bundle of 3 mm diameter fibers. The IR spectrum is filtered out to minimize unnecessary heating at the fiber entrance region. This report describes the following investigations: Niche applications for HSL technology, Luminaire design characteristics for linear and point lighting fixtures, and Daylight affects on productivity.

Byard D. Wood; David L. Beshears

2006-02-01

245

Adaptive Full-Spectrum Solar Energy Systems Cross-Cutting R&D on adaptive full-spectrum solar energy systems for more efficient and affordable use of solar energy in buildings and hybrid photobioreactors  

SciTech Connect

This RD&D project is a multi-institutional effort to develop a hybrid solar lighting (HSL) system that transports daylight from a paraboloidal dish concentrator to a luminaire via a bundle of polymer fiber optics. The luminaire can be a device to distribute sunlight into a space for the production of algae for CO{sub 2} sequestration or it can be a device that is a combination of daylighting and electric lighting for space/task lighting. In this project, the sunlight is collected using a one-meter paraboloidal concentrator dish with two-axis tracking. For the third generation (beta) system, the secondary mirror is an ellipsoidal mirror that directs the visible light into a bundle of 3 mm diameter fibers. The IR spectrum is filtered out to minimize unnecessary heating at the fiber entrance region. This report describes the major achievements from this research that began in August 2001.

Wood, Byard; Kim, Kwang

2006-03-30

246

Engineered Osmosis for Energy Efficient Separations: Optimizing Waste Heat Utilization FINAL SCIENTIFIC REPORT DOE F 241.3  

SciTech Connect

The purpose of this study is to design (i) a stripper system where heat is used to strip ammonia (NH{sub 3}) and carbon dioxide (CO{sub 2}) from a diluted draw solution; and (ii) a condensation or absorption system where the stripped NH{sub 3} and CO{sub 2} are captured in condensed water to form a re-concentrated draw solution. This study supports the Industrial Technologies Program of the DOE Office of Energy Efficiency and Renewable Energy and their Industrial Energy Efficiency Grand Challenge award solicitation. Results from this study show that stimulated Oasys draw solutions composed of a complex electrolyte solution associated with the dissolution of NH{sub 3} and CO{sub 2} gas in water can successfully be stripped and fully condensed under standard atmospheric pressure. Stripper bottoms NH{sub 3} concentration can reliably be reduced to < 1 mg/L, even when starting with liquids that have an NH{sub 3} mass fraction exceeding 6% to stimulate diluted draw solution from the forward osmosis membrane component of the process. Concentrated draw solution produced by fully condensing the stripper tops was show to exceed 6 M-C with nitrogen-to-carbon (N:C) molar ratios on the order of two. Reducing the operating pressure of the stripper column serves to reduce the partial vapor pressure of both NH{sub 3} and CO{sub 2} in solution and enables lower temperature operation towards integration of industrial low-grade of waste heat. Effective stripping of solutes was observed with operating pressures as low as 100 mbar (3-inHg). Systems operating at reduced pressure and temperature require additional design considerations to fully condense and absorb these constituents for reuse within the Oasys EO system context. Comparing empirical data with process stimulation models confirmed that several key parameters related to vapor-liquid equilibrium and intrinsic material properties were not accurate. Additional experiments and refinement of material property databases within the chosen process stimulation software was required to improve the reliability of process simulations for engineering design support. Data from experiments was also employed to calculate critical mass transfer and system design parameters (such as the height equivalent to a theoretical plate (HETP)) to aid in process design. When measured in a less than optimal design state for the stripping of NH{sub 3} and CO{sub 2} from a simulated dilute draw solution the HETP for one type of commercial stripper packing material was 1.88 ft/stage. During this study it was observed that the heat duty required to vaporize the draw solution solutes is substantially affected by the amount of water boilup also produced to achieve a low NH{sub 3} stripper bottoms concentration specification. Additionally, fluid loading of the stripper packing media is a critical performance parameter that affects all facets of optimum stripper column performance. Condensation of the draw solution tops vapor requires additional process considerations if being conducted in sub-atmospheric conditions and low temperature. Future work will focus on the commercialization of the Oasys EO technology platform for numerous applications in water and wastewater treatment as well as harvesting low enthalpy energy with our proprietary osmotic heat engine. Engineering design related to thermal integration of Oasys EO technology for both low and hig-grade heat applications is underway. Novel thermal recovery processes are also being investigated in addition to the conventional approaches described in this report. Oasys Water plans to deploy commercial scale systems into the energy and zero liquid discharge markets in 2013. Additional process refinement will lead to integration of low enthalpy renewable heat sources for municipal desalination applications.

NATHAN HANCOCK

2013-01-13

247

An efficient cryopreservation procedure for potato (Solanum tuberosum L.) utilizing the new ice blocking agent, Supercool X1000.  

PubMed

Cryopreservation has been recognized as a practical and efficient tool for long-term storage of vegetatively propagated plants. This study was conducted to investigate effects of modified vitrification techniques on cryopreservation of potato. In vitro plants of potato cultivars "Superior" and "Atlantic" were cold acclimated, and axillary buds were precultured, osmoprotected, exposed to PVS-2 solution, plunged into liquid nitrogen, thawed, and finally planted in the regeneration medium. In the modified vitrification technique an ice-blocking agent, Supercool X1000, was added with PVS-2 solution. Cold acclimation affected survival of cryopreserved shoot tips, and the highest survival (46.7%) was obtained after 3 weeks of acclimation at 10 degrees C. Shoot tips exposed to 2M glycerol plus 0.6M sucrose for 40 min gave 51.5% and 11.7% survival in "Atlantic" and "Superior" at 10 degrees C, respectively. Cold acclimated and osmoprotected shoot tips were dehydrated with PVS-2 containing different concentrations of Supercool X1000 prior to a plunge into liquid nitrogen. Treatments with 0.1% and 1% of Supercool X1000 significantly improved survival by 55% in "Superior" and 71.3% in "Atlantic", respectively. After cryopreservation, vitrified shoot tips resumed growth within a week in a medium (1 mg l(-1) GA(3), 0.5 mg l(-1) zeatin, and 0.1 mg l(-1) IAA) with a low level of Pluronic F-68 (0.005%) and survival was 33.7% higher in "Atlantic" and 14.7% higher in "Superior" than the control (without Pluronic F-68). PMID:15864594

Zhao, M A; Xhu, Y Z; Dhital, S P; Khu, D M; Song, Y S; Wang, M Y; Lim, H T

2005-10-01

248

Measurements of the modulation transfer function, normalized noise power spectrum and detective quantum efficiency for two flat panel detectors: a fluoroscopic and a cone beam computer tomography flat panel detectors.  

PubMed

The physical performance of two Flat Panel Detectors has been evaluated. The first Flat Panel Detector is for Fluoroscopic applications, Varian PaxScan 2520, and the second is for Cone Beam Computer Tomography applications, Varian PaxScan 4030CB. First, the spectrum of the X-ray source was measured. Second, the linearity of the detectors was investigated by using an ionization chamber and the average ADU values of the detectors. Third, the temporal resolution was characterized by evaluating their image lag. Fourth, their spatial resolution was characterized by the pre-sampling Modulation Transfer Function. Fifth, the Normalized Noise Power Spectrum was calculated for various exposures levels. Finally, the Detective Quantum Efficiency was obtained as a function of spatial frequency and entrance exposure. The results illustrate that the physical performance in Detective Quantum Efficiency and Normalized Noise Power Spectrum of the Cone Beam Computer Tomography detector is superior to that of the fluoroscopic detector whereas the latter detector has a higher spatial resolution as demonstrated by larger values of its Modulation Transfer Function at large spatial frequencies. PMID:19923685

Benítez, Ricardo Betancourt; Ning, Ruola; Conover, David; Liu, Shaohua

2009-01-01

249

Optical performance of dichroic spectrum-splitting filters  

NASA Astrophysics Data System (ADS)

We investigate the optical performance of dichroic filters used in solar spectrum-splitting applications. Photovoltaic (PV) systems utilizing spectrum splitting have higher theoretical conversion efficiency than single-bandgap PV modules. Dichroic filters have been used in several spectrum-splitting optical system designs with success. However, dichroic filters only achieve ideal performance under collimated incident light. With an incident angle constraint the optical concentration ratio is limited. A high-concentration ratio helps to achieve high-conversion efficiency and control cost by reducing the PV cell area. In a dual-junction spectrum-splitting PV configuration with a gallium arsenide (GaAs) PV cell and a 2.1-eV bandgap PV cell, the experimental dichroic filter can provide 86.3% of the ideal designed performance. The filter nonideal performance under focused incident light is simulated with ZEMAX. System efficiency under different F-number and filter refractive index is simulated for dual-junction and three-junction systems to show the performance of dichroic filters. We have found that for a dual-bandgap spectrum-splitting system there is a 0.32% system efficiency gain associated with a filter refractive index increased from 1.5 to 1.95. An efficiency gain of 0.41% is associated with an aperture size reduction from F2.0 to F3.0. In a three-junction configuration, simulation shows that a 0.57% system efficiency gain is possible when the filter refractive index is increased from 1.5 to 1.95. An efficiency gain of 0.63% is associated with an aperture size reduction from F2.0 to F3.0.

Zhang, Deming; Wu, Yuechen; Russo, Juan M.; Gordon, Michael; Vorndran, Shelby; Kostuk, Raymond K.

2014-01-01

250

Evaluation of Efficiency of Screening Extended-Spectrum ?-Lactamase-Producing Escherichia coli and Klebsiella pneumoniae in Hospitals Where the Bacteria Are Increasingly Prevalent  

PubMed Central

The disk screening methods for extended-spectrum ?-lactamase-producing strains were evaluated. The confirmatory work is reduced significantly in settings such as those in this study, by changing the cefpodoxime breakpoint to ?20 mm and by not testing cefoxitin-resistant isolates. Cefotaxime and ceftazidime disk screening is reliable, and the laboratory-prepared cefotaxime- and ceftazidime-clavulanic acid disks are stable at ?20°C for 12 weeks.

Lee, K.; Lim, J. K.; Yong, D.; Yum, J.; Chong, Y.; Okamoto, R.; Inoue, M.

2001-01-01

251

Enhancement of the luminance efficiency in blue organic light-emitting devices fabricated utilizing a hybrid phosphorescence and fluorescence emitting layer  

Microsoft Academic Search

Blue organic light-emitting devices (OLEDs) fabricated utilizing a hybrid emitting layer (EML) consisting of a bis(3,5-difluoro-2-(2-pyridyl)phenyl-(2-carboxypyridyl)iridiumIII (FIrpic)-doped 1,3-bis(carbazol-9-yl)benzene (mCP) layer, a 2-methyl-9,10-bis(naphthalene-2-yl)anthracene (MADN)-doped mCP layer, and a 2,9-dimethyl-4,7-diphenyl-1,10-phenanthorlene (BCP)-doped MADN layer were fabricated to investigate their luminance efficiency enhancement. The FIrpic-doped mCP layer, the MADN-doped mCP layer, and the BCP-doped MADN layer in the blue OLEDs acted as a phosphorescence

Hyun Sung Bang; Hwan Seok Jeong; Dong Chul Choo; Tae Whan Kim

2011-01-01

252

ADAPTIVE FULL-SPECTRUM SOLAR ENERGY SYSTEMS CROSS-CUTTING R&D ON ADAPTIVE FULL-SPECTRUM SOLAR ENERGY SYSTEMS FOR MORE EFFICIENT AND AFFORDABLE USE OF SOLAR ENERGY IN BUILDINGS AND HYBRID PHOTOBIOREACTORS  

SciTech Connect

This RD&D project is a three year team effort to develop a hybrid solar lighting (HSL) system that transports daylight from a paraboloidal dish concentrator to a luminaire via a bundle of small core or a large core polymer fiber optics. The luminaire can be a device to distribute sunlight into a space for the production of algae or it can be a device that is a combination of daylighting and electric lighting for space/task lighting. In this project, the sunlight is collected using a one-meter paraboloidal concentrator dish with two-axis tracking. For the second generation (alpha) system, the secondary mirror is an ellipsoidal mirror that directs the visible light into a bundle of small-core fibers. The IR spectrum is filtered out to minimize unnecessary heating at the fiber entrance region. This report describes the following investigations of various aspects of the system: (1) Performance specifications were developed for the tracking subsystem and collector optics, (2) Thermal management experiments for the fiber optic bundle entrance region, and (3) Bioreactor testing, cost-modeling, and redesign. Much of the planned work has been slowed due to significant procurement delays of the primary mirror. However, taken as a whole, they do confirm progress towards the technical feasibility and commercial viability of this technology. Due to this procurement delay, a no-cost extension of the project completion date has been requested and approved.

Byard D. Wood; Jeff D. Muhs

2005-02-01

253

Collusion-Resistant Multi-Winner Spectrum Auction for Cognitive Radio Networks.  

National Technical Information Service (NTIS)

In order to fully utilize spectrum, auction-based dynamic spectrum allocation has become a promising approach which allows unlicensed wireless users to lease unused bands from spectrum license holders. Because spectrum resources are reusable by users far ...

B. Wang, K. J. Liu, T. C. Clancy, Y. Wu

2008-01-01

254

The Min System and Nucleoid Occlusion Are Not Required for Identifying the Division Site in Bacillus subtilis but Ensure Its Efficient Utilization  

PubMed Central

Precise temporal and spatial control of cell division is essential for progeny survival. The current general view is that precise positioning of the division site at midcell in rod-shaped bacteria is a result of the combined action of the Min system and nucleoid (chromosome) occlusion. Both systems prevent assembly of the cytokinetic Z ring at inappropriate places in the cell, restricting Z rings to the correct site at midcell. Here we show that in the bacterium Bacillus subtilis Z rings are positioned precisely at midcell in the complete absence of both these systems, revealing the existence of a mechanism independent of Min and nucleoid occlusion that identifies midcell in this organism. We further show that Z ring assembly at midcell is delayed in the absence of Min and Noc proteins, while at the same time FtsZ accumulates at other potential division sites. This suggests that a major role for Min and Noc is to ensure efficient utilization of the midcell division site by preventing Z ring assembly at potential division sites, including the cell poles. Our data lead us to propose a model in which spatial regulation of division in B. subtilis involves identification of the division site at midcell that requires Min and nucleoid occlusion to ensure efficient Z ring assembly there and only there, at the right time in the cell cycle.

Rodrigues, Christopher D. A.; Harry, Elizabeth J.

2012-01-01

255

Power Generation Efficiency of Photovoltaics and a SOFC-PEFC Combined Micro-grid with Time Shift Utilization of the SOFC Exhaust Heat  

NASA Astrophysics Data System (ADS)

In this study, the combined system of a solid-oxide fuel cell (SOFC) and a proton-exchange membrane fuel cell (PEFC) is developed. The proposed system consists of a SOFC-PEFC combined system and a photovoltaic system (PV) as the energy supply to a micro-grid. The exhaust heat of the SOFC is used for the steam reforming of the bio-ethanol gas with time shift utilization of the exhaust heat of the SOFC in optional time. The SOFC-PEFC combined system with the PV was introduced in a micro-grid of 30 residences in Sapporo, Japan. The operation plan of the system has three cases: without solar power, with 50% and with 100% of solar output power. Moreover, three types of system operation of using the SOFC independent operation, PEFC independent operation and SOFC-PEFC combined system are used to supply the demand side. A comparative study between the types of system operation is presented. The power generation efficiency is investigated for different load patterns: average load pattern, compressed load pattern and extended load pattern. This paper reported that the power generation efficiencies of the proposedsystem in consideration of these load patterns are 27% to 48%.

El-Sayed, Abeer Galal; Obara, Shin'ya

256

A preliminary report on the photoionization efficiency spectrum, ionization energy and heat of formation of Br{sub 2}O; and the appearance energy of BrO{sup +} (Br{sub 2}O)  

SciTech Connect

We report experimental results for the photoionization efficiency (PIE) spectrum of Br{sub 2}O along with the ionization energy (derived form the ionization threshold) and the appearance energy (AE) of BrO{sup +} (Br{sub 2}O). A value for the heat of formation of Br{sub 2}O is derived form the AE result. Experiments were performed by employing a discharge flow-photoionization mass spectrometer (DF-PIMS) apparatus coupled to beamline U-11 at the National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory.

Thorn, R.P. Jr.; Monks, P.S.; Stief, L.J.; Kuo, S.C.; Zhang, Z.; Klemm, R.B.

1995-08-01

257

Threshold Based Call Admission Control for QoS Provisioning in Cellular Wireless Networks with Spectrum Renting  

Microsoft Academic Search

\\u000a Radio spectrum is scarce and precious resource in wireless networks. To efficiently utilize radio spectrum, idle radio channels\\u000a can be rented between various wireless networks and a wireless network renting out its idle channels can withdraw its radio\\u000a channels when requiring its channels. However, the rental and withdrawal of radio channels result in two phenomena. One is\\u000a the variation in

Show-Shiow Tzeng; Ching-Wen Huang

2008-01-01

258

Roll-to-roll cohesive, coated, flexible, high-efficiency polymer light-emitting diodes utilizing ITO-free polymer anodes.  

PubMed

This paper reports solution-processed, high-efficiency polymer light-emitting diodes fabricated by a new type of roll-to-roll coating method under ambient air conditions. A noble roll-to-roll cohesive coating system utilizes only natural gravity and the surface tension of the solution to flow out from the capillary to the surface of the substrate. Because this mechanism uses a minimally cohesive solution, the roll-to-roll cohesive coating can effectively realize an ultra-thin film thickness for the electron injection layer. In addition, the roll-to-roll cohesive coating enables the fabrication of a thicker polymer anode film more than 250 nm at one time by modification of the surface energy and without wasting the solution. It is observed that the standard sheet resistance deviation of the polymer anode is only 2.32 ?/? over 50 000 bending cycles. The standard sheet resistance deviation of the polymer anode in the different bending angles (0 to 180°) is 0.313 ?/?, but the case of the ITO-PET is 104.93 ?/?. The average surface roughness of the polymer anode measured by atomic force microscopy is only 1.06 nm. Because the surface of the polymer anode has a better quality, the leakage current of the polymer light-emitting diodes (PLEDs) using the polymer anode is much lower than that using the ITO-PET substrate. The luminous power efficiency of the two devices is 4.13 lm/W for the polymer anode and 3.21 lm/W for the ITO-PET. Consequently, the PLEDs made by using the polymer anode exhibited 28% enhanced performance because the polymer anode represents not only a higher transparency than the ITO-PET in the wavelength of 560 nm but also greatly reduced roughness. The optimized the maximum current efficiency and power efficiency of the device show around 6.1 cd/A and 5.1 lm/W, respectively, which is comparable to the case of using the ITO-glass. PMID:23784859

Shin, Seongbeom; Yang, Minyang; Guo, L Jay; Youn, Hongseok

2013-12-01

259

[Design of concave grating for ultraviolet-spectrum].  

PubMed

Ultraviolet-spectrum technology is a kind of low signal and multianalysis technology. For taking full advantage of spectral information and reducing the volume of spectrometer, we used high efficiency spectroscopy structure based on concave grating. Based on concave grating theory and optic design software ZEMAX, a flat field concave grating for ultraviolet spectrophotometer was designed from primary structure, which relied on global optimization of the software. The contradiction between wide spectrum bound and limited spectrum extension was resolved, aberrations were reduced successfully, spectrum information was utilized fully, and the optic structure of spectrometer was highly efficient. For better preference of this spectrophotometer, after get the structure parameter, combine grating fabrication condition with practice working condition, grating diffractive theory, holographic optics theory and software PCG rate was used for diffraction efficiency design and improve. A paradigm of flat field concave grating is given, it works between 190 nm to 410 nm, the diameter of the concave grating is 20 mm, and F/# is 0.21. The design result was analyzed and evaluated. It was showed that if the slit source, whose width is 50 microm, is used to reconstruction, the theoretic resolution capacity is better than 3 nm. PMID:22870673

Luo, Biao; Wen, Zhi-Yu; Wen, Zhong-Quan; Zeng, Tian-Ling

2012-06-01

260

Wireless Communication Spectrum Guidelines for ITS.  

National Technical Information Service (NTIS)

In this research presentation, the Hata-Okumura model is used as the basis of deriving a suitable RF propagation model for the spread spectrum environment. Spread spectrum results in efficient spectrum use, and today the FCC designated frequency band of 2...

1999-01-01

261

Spectrum allocation strategies for heterogeneous networks  

Microsoft Academic Search

This work analyzed the trade-off between the area spectral efficiency and outage user rates in heterogeneous cel- lular networks with overlapping picocells. We considered two different models for the spectrum allocation and cell association. The first model employs a spectrum overlapping strategy with an SINR-based cell association. The second model avoids the interference between macrocell and picocell through a spectrum

Rindra Ramamonjison; Kei Sakaguchi; Kiyomichi Araki; Shoji Kaneko; Yoji Kishi; Noriaki Miyazaki

2011-01-01

262

Dynamic Spectrum Access to the Combined Resource of Commercial and Public Safety Bands Based on a WCDMA Shared Network  

NASA Astrophysics Data System (ADS)

The public safety spectrum is generally under-utilized due to the unique traffic characteristics of bursty and mission critical. This letter considers the application of dynamic spectrum access (DSA) to the combined spectrum of public safety (PS) and commercial (CMR) users in a common shared network that can provide both PS and CMR services. Our scenario includes the 700MHz Public/Private Partnership which was recently issued by the Federal Communications Commission. We first propose an efficient DSA mechanism to coordinate the combined spectrum, and then establish a call admission control that reflects the proposed DSA in a wideband code division multiple access based network. The essentials of our proposed DSA are opportunistic access to the public safety spectrum and priority access to the commercial spectrum. Simulation results show that these schemes are well harmonized in various network environments.

Jeon, Hyoungsuk; Im, Sooyeol; Kim, Youmin; Kim, Seunghee; Kim, Jinup; Lee, Hyuckjae

263

Design, fabrication, and characterization of polymer based bulk heterojunction solar cells with enhanced efficiencies  

Microsoft Academic Search

Polymer based bulk heterojunction (BHJ) solar cells offer promising technological advantages for actualization of low-cost and large-area fabrication on flexible substrates. To reach the envisaged market entry figure of 10% power conversion efficiency (PCE), it is crucial that more solar energy is utilized in the active layer, requiring both higher energy conversion efficiency and expansion of the absorption spectrum of

Haiwei Lu

2008-01-01

264

An efficient demand-assignment multiple access protocol for wireless packet (ATM) networks  

Microsoft Academic Search

In a wireless packet (ATM) network that supports an integrated mix of multimedia traffic, the channel access protocol needs to be designed such that mobiles share the limited communications bandwidth in an efficient manner: maximizing the utilization of the frequency spectrum and minimizing the delay experienced by mobiles. In this paper, we propose and study an efficient demand-assignment channel access

Mark J. Karol; Kai Y. Eng; Zhao Liu

1995-01-01

265

Biomass utilization  

SciTech Connect

Forty papers are presented in 6 sections: Biomass utilization - the concept; The raw material and its preparation; The structure and chemical composition of biomass; Conversion methods - biological; Conversion methods - thermochemical; and Engineering and economics in biomass utilization. Ten papers are of particular forestry interest: Forest inventories as the basis for a continuous monitoring of forest biomass resources (Cunia, T.); Aerial photo biomass equation (Kasile, J.); Forest biomass utilization in Greece (Tsoumis, C.); Mass propagation of selected trees for biomass by tissue culture (Venketeswaran, S. et al.); The anatomy, ultrastructure and chemical composition of wood (Coete, W.A.); Some structural characteristics of acid hydrolysis lignins (Papadopoulos, J.); Thermochemical routes to chemicals, fuels and energy from forestry and agricultural residues (Soltes, E.J.); Pyrolysis of wood wastes (Figueiredo, J.L. et al.); Efficient utilization of woody biomass: a cellulose-particleboard-synfuels model (Young, R.A.; Achmadi, S.); and Methanol from wood, a state of the art review (Beenackers, A.A.C.M.; Swaaij, W.P.M. van).

Coute, W.A. (ed.)

1983-01-01

266

Etiquette Modification for Unlicensed Spectrum: Approach and Impact1  

Microsoft Academic Search

In unlicensed spectrum, any device is free to transmit without a government license that implies exclusive access. Such spectrum has significant benefits, but serious challenges must first be overcome. Foremost is the risk of drastic performance degradation and inefficient spectrum utilization, due to a lack of incentive to conserve shared spectrum. Previous work (8) has shown this problem to be

Durga P. Satapathy; Jon M. Peha

1998-01-01

267

Dangers of Excessive Resource Consumption in Unlicensed Spectrum1  

Microsoft Academic Search

There are growing opportunities for the wireless industry to deploy products in unlicensed spectrum, where no licensing is required and devices share spectrum. Unlicensed spectrum offers significant benefits, but there are serious challenges to overcome before these benefits can be fully realized. Foremost among these is the risk of serious performance degradation and inefficient spectrum utilization, resulting from a lack

Durga P. Satapathy; Jon M. Peha

268

Etiquette modification for unlicensed spectrum: approach and impact  

Microsoft Academic Search

In the unlicensed spectrum, any device is free to transmit without a government license that implies exclusive access. Such spectrum has significant benefits, but serious challenges must first be overcome. Foremost is the risk of drastic performance degradation and inefficient spectrum utilization, due to a lack of incentive to conserve shared spectrum. Previous work has shown this problem to be

Durga P. Satapathy; Jon M. Peha

1998-01-01

269

Sharing government spectrum with private users: opportunities and challenges  

Microsoft Academic Search

Measurements of spectrum occupancy typically confirm the expectation that spectrum assigned to government entities often has low average utilization in urban areas despite its potential for peaks during emergencies. By contrast, spectrum assigned to the private sector is usually most heavily used in urban areas. The second generation of government spectrum sharing started in 2004 with cognitive-radio-based sharing of the

Michael Marcus

2009-01-01

270

Weatherization Partnerships Project, Grant No. DE FG 0299EE27594, October 1, 1999 - December 31, 2000. Final Technical Report and FY 1999 version of 'Lessons learned the long way: Integrating utility, energy efficiency tasks with weatherization'  

SciTech Connect

Includes reports on (1) the results of focus groups on managing utility residential efficiency [attitudes?] for low-income housing, and (2) low-income household energy consumption and expenditures patterns and weatherization opportunities 1987-1997, intensive analysis of R.E.C.S. data.

Power, Meg

2002-11-01

271

A discharge flow-photoionization mass spectrometric study of the FO(X 2 Pi i) radical. Photoionization efficiency spectrum and ionization energy  

NASA Technical Reports Server (NTRS)

Photoionization efficiency spectra of FO were measured over the wavelength range 80.0-100.0 nm and in the ionization threshold region, 94.0-100.0 nm, using a discharge flow-photoionization mass spectrometer apparatus coupled to a synchrotron radiation source. FO was generated by the reaction of F2P atoms with NO3 and via a F2O2 discharge. A value of 12.78 +/- 0.03 eV was obtained for the adiabatic ionization energy of FO from photoion thresholds which corresponds to FO(+)(X 3 Sigma -) from FO(X 2 Pi i). These results, which are the first to be obtained by direct Photo-ionization mass spectrometry (PIMS) measurements, corroborate those of a photoelectron spectroscopy (PES) study; however, the ionization energy determined here is free from interferences due to other species which complicated the PES measurement. A value of 109.5 +/- 8.0 kJ/mol for Delta f H 0 298(FO) is computed from the present value of IE(FO) and a previous appearance energy measurement, and a value for the proton affinity of FO is calculated to be 511.5 +/- 10.0 kJ/mol.

Zhang, Zhengyu; Kuo, Szu-Cherng; Klemm, R. Bruce; Monks, Paul S.; Stief, Louis J.

1994-01-01

272

A Saw-Based Spread Spectrum Wireless Lan System  

Microsoft Academic Search

In Japan, the spread spectrum wireless LAN is prospected to be approved by February 1993. Utilizing a new type SAW device, we succeeded in developing the spread spectrum wireless LAN system. Its data ratio is a 230-kbps.

Kazuyuki TAKEHARA; Toshiyuki TANAKA; K. Okada; T. Tada

1992-01-01

273

Spectrum formation in supernovae - Numerical techniques  

NASA Technical Reports Server (NTRS)

The study combines several novel techniques for spectrum simulation in the Eddington computer program which solves the comoving frame equation of transfer coupled with the statistical and radiative equilibrium equations. One of these is a generalization of the accelerated lambda iteration (ALI) scheme to include an approximate frequency-derivative operator. This greatly enhances the convergence rate of ALI in optically thick, high-velocity shear flows. Another is a partial linearization technique which is capable of efficiently solving a very large number of rate equations on a moderately sized computer. An expansion opacity and emissivity approximation is derived which makes it possible to determine the effect on the transfer and statistical equilibrium of a very large number of lines not explicitly represented in the frequency grid and additionally to treat line-blanketing from species not explicitly included in the rate equations. The utility of these techniques is illustrated with models of two supernovae.

Eastman, Ronald G.; Pinto, Philip A.

1993-01-01

274

Visible Spectrum Incandescent Selective Emitter  

SciTech Connect

The purpose of the work performed was to demonstrate the feasibility of a novel bi-layer selective emitter. Selective emitters are incandescent radiant bodies with emissivities that are substantially larger in a selected part of the radiation spectrum, thereby significantly shifting their radiated spectral distribution from that of a blackbody radiating at the same temperature. The major research objectives involved answering the following questions: (1) What maximum VIS/NIR radiant power and emissivity ratios can be attained at 2650 K? (2) What is the observed emitter body life and how does its performance vary with time? (3) What are the design tradeoffs for a dual heating approach in which both an internally mounted heating coil and electrical resistance self-heating are used? (4) What are the quantitative improvements to be had from utilizing a bi-layer emitter body with a low emissivity inner layer and a partially transmissive outer layer? Two approaches to obtaining selective emissivity were investigated. The first was to utilize large optical scattering within an emitter material with a spectral optical absorption that is much greater within the visible spectrum than that within the NIR. With this approach, an optically thick emitter can radiate almost as if optically thin because essentially, scattering limits the distance below the surface from which significant amounts of internally generated radiation can emerge. The performance of thin emitters was also investigated (for optically thin emitters, spectral emissivity is proportional to spectral absorptivity). These emitters were fabricated from thin mono-layer emitter rods as well as from bi-layer rods with a thin emitter layer mounted on a substrate core. With an initially estimated energy efficiency of almost three times that of standard incandescent bulbs, a number of energy, economic and environmental benefits such as less energy use and cost, reduced CO{sub 2} emissions, and no mercury contamination was initially projected. The work performed provided answers to a number of important questions. The first is that, with the investigated approaches, the maximum sustained emitter efficiencies are about 1.5 times that of a standard incandescent bulb. This was seen to be the case for both thick and thin emitters, and for both mono-layer and bi-layer designs. While observed VIS/NIR ratios represent improvements over standard incandescent bulbs, it does not appear sufficient to overcome higher cost (i.e. up to five times that of the standard bulb) and ensure commercial success. Another result is that high temperatures (i.e. 2650 K) are routinely attainable without platinum electrodes. This is significant for reducing material costs. A novel dual heating arrangement and insulated electrodes were used to attain these temperatures. Another observed characteristic of the emitter was significant grain growth soon after attaining operating temperatures. This is an undesirable characteristic that results in substantially less optical scattering and spectral selectivity, and which significantly limits emitter efficiencies to the values reported. Further work is required to address this problem.

Sonsight Inc.

2004-04-30

275

Effectiveness and energy efficiency of the Utility and Energy Monitoring and Control System (UEMCS). Foreign trip report, September 18--October 3, 1992.  

National Technical Information Service (NTIS)

The travelers, representing the ORNL Energy Division, conducted an in-depth evaluation of the Utilities and Energy Monitoring and Control System (UEMCS) installed at the U. S. Army Europe (USAREUR) Hohenfels Military Community. The system investigated is ...

M. B. Gettings P. A. Tapp

1992-01-01

276

Error correction coding for frequency-hopping multiple-access spread spectrum communication systems  

NASA Technical Reports Server (NTRS)

A communication system which would effect channel coding for frequency-hopped multiple-access is described. It is shown that in theory coding can increase the spectrum utilization efficiency of a system with mutual interference to 100 percent. Various coding strategies are discussed and some initial comparisons are given. Some of the problems associated with implementing the type of system described here are discussed.

Healy, T. J.

1982-01-01

277

[A method for measuring emission spectrum of YAG phosphor used in LED white light under practical conditions].  

PubMed

A new method for measuring the emission spectra of the YAG phosphor under blue light excitation was proposed. Utilizing the Gaussian function and Fermi function fitting and simulated annealing optimization techniques, mathematical fitting functions for matching mixed emission spectrum were obtained. And so, the emission spectrum of the YAG phosphor was separated, further its luminescence properties can be characterized. Our experiment results proved that its characteristic parameters present non-negligible differences. The optical metric differences such as those in quantum efficiency, light emitting efficiency and energy efficiency are higher than 1%. The difference in CCT (correlated color temperature) is up to tens of K, and chromaticity indicators also produce differences in chromaticity coordinates, dominant wavelength and color purity. But little change is there in the half-peak bandwidth, and peak wavelength is basically unaffected. All these show that the established method can improve the measurement accuracy of YAG yellow phosphor emission spectrum under practical conditions. PMID:24059185

Xu, Yan-Fang; Zhang, Guo-Sheng; Li, Lu-Hai; Ding, Ying-Kun

2013-07-01

278

Bursty Traffic in Energy-Constrained Opportunistic Spectrum Access.  

National Technical Information Service (NTIS)

We design opportunistic spectrum access strategies for improving spectrum efficiency. In each slot, a secondary user chooses a subset of channels to sense and decides whether to access based on the sensing outcomes. Incorporating the secondary user's resi...

A. Swami Q. Zhao Y. Chen

2007-01-01

279

Final Report for DE-FG36-08GO18007 "All-Inorganic, Efficient Photovoltaic Solid State Devices Utilizing Semiconducting Colloidal Nanocrystal Quantum Dots"  

SciTech Connect

We demonstrated robust colloidal quantum dot (QD) photovoltaics with high internal quantum efficiencies. In our structures, device durability is derived from use of all-inorganic atmospherically-stable semiconducting metal-oxide films together with QD photoreceptors. We have shown that both QD and metal-oxide semiconducting films and contacts are amenable to room temperature processing under minimal vacuum conditions, enabling large area processing of PV structures of high internal efficiency. We generated the state of the art devices with power conversion efficiency of more than 4%, and have shown that efficiencies as high as 9% are achievable in the near-term, and as high as 17% in the long-term.

Vladimir Bulovic and Moungi Bawendi

2011-09-30

280

Hybrid spread spectrum radio system  

DOEpatents

Systems and methods are described for hybrid spread spectrum radio systems. A method includes modulating a signal by utilizing a subset of bits from a pseudo-random code generator to control an amplification circuit that provides a gain to the signal. Another method includes: modulating a signal by utilizing a subset of bits from a pseudo-random code generator to control a fast hopping frequency synthesizer; and fast frequency hopping the signal with the fast hopping frequency synthesizer, wherein multiple frequency hops occur within a single data-bit time.

Smith, Stephen F. (London, TN); Dress, William B. (Camas, WA)

2010-02-02

281

Genome Sequence of Enterobacter cloacae subsp. dissolvens SDM, an Efficient Biomass-Utilizing Producer of Platform Chemical 2,3-Butanediol  

PubMed Central

Enterobacter cloacae subsp. dissolvens SDM has an extraordinary characteristic of biomass utilization for 2,3-butanediol production. Here we present a 4.9-Mb assembly of its genome. The key genes for regulation and metabolism of 2,3-butanediol production were annotated, which could provide further insights into the molecular mechanism of high-yield production of 2,3-butanediol.

Xu, Youqiang; Wang, Ailong; Tao, Fei; Su, Fei; Tang, Hongzhi

2012-01-01

282

GUIDELINES FOR NOX CONTROL BY COMBUSTION MODIFICATION FOR COAL-FIRED UTILITY BOILERS. PROCEDURES FOR REDUCTION OF NOX EMISSIONS AND MAXIMIZATION OF BOILER EFFICIENCY  

EPA Science Inventory

The report, which has been reviewed by industry experts, reflects the experience developed in successfully applying combustion modifications to reduce NOx emissions from coal-fired utility boilers. Although the report emphasizes coal-fired equipment, the same principles can be ap...

283

A cognitive approach to spectrum sensing in virtual unlicensed wireless network  

Microsoft Academic Search

Today's wireless networks are characterized by a fixed spectrum assignment policy. However, a large portion of the assigned spectrum is used sporadically and geographical variations in the utilization of assigned spectrum ranges from 15% to 85% with a high variance in time. The limited available spectrum and the inefficiency in the spectrum usage necessitate a new communication paradigm to exploit

Sunita S. Barve; S. B. Deosarkar; Sonal A. Bhople

2009-01-01

284

Efficient production of L-lactic acid from corncob molasses, a waste by-product in xylitol production, by a newly isolated xylose utilizing Bacillus sp. strain.  

PubMed

Lignocellulosic biomass-derived sugars are considered nowadays to be an economically attractive carbohydrate feedstock for large-scale fermentations of bulk chemicals such as lactic acid. In the present study, corncob molasses containing a high content of xylose, which is one of the lignocellulosic biomasses and a waste by-product from xylitol production, was used for L-lactic acid production via a newly isolated xylose utilizing Bacillus sp. strain XZL9. Bacillus sp. strain XZL9 can utilize the mixture of sugars including xylose, arabinose, and glucose in corncob molasses for L-lactic acid production. High concentration of L-lactic acid (74.7 g l?¹) was obtained from corncob molasses (initial total sugars of 91.4 g l?¹) in fed-batch fermentation. This study provides an encouraging means of producing L-lactic acid from lignocellulosic resource such as the low-cost corncob molasses. PMID:20627714

Wang, Limin; Zhao, Bo; Liu, Bo; Yu, Bo; Ma, Cuiqing; Su, Fei; Hua, Dongliang; Li, Qinggang; Ma, Yanhe; Xu, Ping

2010-10-01

285

Spectrum Survey in Singapore: Occupancy Measurements and Analyses  

Microsoft Academic Search

We study the 24-hour spectrum usage pattern in Singapore in the frequency bands ranging from 80 MHz to 5850 MHz. The objectives are to find how the scarce radio spectrum allocated to different services is utilized in Singapore and identify the bands that could be accessed for future opportunistic use due to their low or no active utilization. The results

M. H. Islam; C. L. Koh; S. W. Oh; Xianming Qing; Y. Y. Lai; Cavin Wang; Ying-Chang Liang; B. E. Toh; F. Chin; G. L. Tan; W. Toh

2008-01-01

286

The allocation of the radio spectrum  

NASA Astrophysics Data System (ADS)

The system of the radio spectrum (10 kHz-300 GHz) allocation is discussed in its technical, economic, and managerial aspects. Possible improvements to the system are considered, such as minimizing human management, establishing a single authority for the allocation of the spectrum, and stimulating a more efficient use of the spectrum with economic incentives. The 'anarchy band' concept, a system of dynamic allocation, is suggested as a means of replacing human management with electronic equipment. The growing importance of the satellite portion of the spectrum is also shown.

Jackson, C. L.

1980-02-01

287

Effects of Pectin and Cellulose on Growth, Feed Efficiency, and Protein Utilization, and their Contribution to Energy Requirement and Cecal VFA in Rats  

Microsoft Academic Search

Graded levels of cellulose (0 to 20%) or of pectin (0 to 10%) were incorporated in purified diets with either 22 or 8.5% casein as the protein source. Weanling male rats were fed these diets for 4 weeks. Body weight gain, food consumption, feed efficiency, protein biological value, apparent digestion of food, fiber and protein, cecal weight and cecal volatile

EDWIN L. HOVE

288

High efficiency 2 micrometer laser utilizing wing-pumped Tm.sup.3+ and a laser diode array end-pumping architecture  

DOEpatents

Wing pumping a Tm.sup.3+ doped, end pumped solid state laser generates 2 .mu.m laser radiation at high average powers with high efficiency. Using laser diode arrays to end-pump the laser rod or slab in the wing of the Tm.sup.3+ absorption band near 785 nm results in 2-for-1 quantum efficiency in Tm.sup.3+ because high Tm.sup.3+ concentrations can be used. Wing pumping allows the thermal power generated in the rod or slab to be distributed over a large enough volume to make thermal management practical in the laser gain medium even at high average power operation. The approach is applicable to CW, Q-switched, and rep-pulsed free-laser operation.

Beach, Raymond J. (Livermore, CA)

1997-01-01

289

White tea consumption slightly reduces iron absorption but not growth, food efficiency, protein utilization, or calcium, phosphorus, magnesium, and zinc absorption in rats.  

PubMed

We investigated the antinutritional effect of white tea extract (0, 15, and 45 mg of the tea solid extract per kilogram body weight) incorporated in the drinking water of rats for 3 and 30 days. Gender-based differences were found for all these variables, except apparent protein digestibility and the apparent absorption of calcium, phosphorus, and iron. White tea extract consumption did not significantly change body weight gain, food intake, food efficiency, protein efficiency ratio, apparent protein digestibility, nitrogen balance, or the apparent absorption of calcium, phosphorus, magnesium, and zinc. Nevertheless, the apparent absorption of iron was slightly (15-18%) but significantly (P<0.05) lower in rats that consumed white tea at the highest dose compared with the control groups at both 3 and 30 days. Our results suggest that the usual consumption of white tea is safe, although its effect on long-term iron absorption at high doses warrants more detailed investigation. PMID:21336649

Pérez-Llamas, Francisca; González, Daniel; Cabrera, Lorena; Espinosa, Cristobal; López, Jose A; Larqué, Elvira; Almajano, M Pilar; Zamora, Salvador

2011-09-01

290

High-efficiency organic light-emitting diodes utilizing thermally activated delayed fluorescence from triazine-based donor-acceptor hybrid molecules  

NASA Astrophysics Data System (ADS)

We have designed and synthesized a high-efficiency purely organic luminescent material, 2,4-bis{3-(9 H-carbazol-9-yl)-9 H-carbazol-9-yl}-6-phenyl-1,3,5-triazine (CC2TA) comprising the bicarbazole donor and phenyltriazine acceptor units, which is capable of emitting thermally activated delayed fluorescence. The molecular design of CC2TA allows spatial separation of HOMO and LUMO on the donor and acceptor fragments, respectively, leading to an exceptionally small singlet-triplet exchange energy (?EST = 0.06 eV) together with a high triplet energy. Furthermore, a high external electroluminescence quantum efficiency as high as 11% +/- 1% has been achieved in the sky-blue organic light-emitting diodes employing CC2TA as an emitter.

Youn Lee, Sae; Yasuda, Takuma; Nomura, Hiroko; Adachi, Chihaya

2012-08-01

291

High efficiency 2 micrometer laser utilizing wing-pumped Tm{sup 3+} and a laser diode array end-pumping architecture  

DOEpatents

Wing pumping a Tm{sup 3+} doped, end pumped solid state laser generates 2 {micro}m laser radiation at high average powers with high efficiency. Using laser diode arrays to end-pump the laser rod or slab in the wing of the Tm{sup 3+} absorption band near 785 nm results in 2-for-1 quantum efficiency in Tm{sup 3+} because high Tm{sup 3+} concentrations can be used. Wing pumping allows the thermal power generated in the rod or slab to be distributed over a large enough volume to make thermal management practical in the laser gain medium even at high average power operation. The approach is applicable to CW, Q-switched, and rep-pulsed free-laser operation. 7 figs.

Beach, R.J.

1997-11-18

292

Nanoparticles for solar spectrum conversion  

NASA Astrophysics Data System (ADS)

We review the use of nanometer-sized particles (including quantum dots) in the conversion of parts of the solar spectrum incident on solar cells to more usable regions. The modification of the solar spectrum ideally would lead to a narrowbanded incident spectrum at a center wavelength corresponding to an energy that is slightly larger than the band gap of the semiconductor material employed in the solar cell, which would lead to an enhancement of the overall solar energy conversion efficiency. Modification of the spectrum requires down and/or up conversion or shifting of the spectrum, meaning that the energy of photons is modified either to lower (down) or higher (up) energy. Nanostructures such as quantum dots, luminescent dye molecules, and lanthanide-doped glasses are capable of absorbing photons at a certain wavelength and emitting photons at a different (shorter or longer) wavelength. We will discuss down and up conversion and shifting by quantum dots, luminescent dyes, and lanthanide compounds, and assess their potential in contributing to ultimately lowering the cost per kWh of solar generated power.

van Sark, Wilfried G. J. H. M.; Meijerink, Andries; Schropp, Ruud E. I.

2010-08-01

293

The Electromagnetic Spectrum  

NSDL National Science Digital Library

This web site contains materials about all parts of the electromagnetic spectrum. It describes each space telescope that NASA has launched as well as its observing range in the electromagnetic spectrum.

Astrophysics, Laboratory F.

2004-11-17

294

Performance of Reed-Solomon Coded Frequency-Hop Spread-Spectrum Communications in Partial-Band Interference  

Microsoft Academic Search

This paper is concerned with the performance of a Communications system which utilizes frequency-hop spread spectrum, diversity transmission, Reed-Solomon coding, and parallel error-correction and erasure-correction decoding. Both binary signaling andM-ary orthogonal signaling are considered. The goals are twofold. First, it is desirable to provide good performance in partial-band Gaussian noise interference by use of coding and diversity with an efficient

MICHAEL B. PURSLEY; WAYNE E. STARK

1985-01-01

295

Nde: Surfing the Electromagnetic Spectrum  

NASA Astrophysics Data System (ADS)

Advances in Nondestructive Evaluation demand an arsenal of techniques. This was as true twenty years ago as it is today. As materials and their associated technologies progress, so must the strategy for evaluating the quality of the product. Nondestructive Evaluation is a constant struggle to extract, from classical and quantum physics, the quintessential elements that will optimally address an inspection requirement, apart from purely academic interest. It must work to be useful and thereby advance the field. The electromagnetic spectrum, from Roentgen to Maxwell/Hertz, lies at the foundation of both classical and quantum physics. Not only has NDE plucked pearls form every nook of the spectrum ranging from X-rays to T-rays but also has managed to utilize virtually every known coupling of the spectrum to the classical mechanics of heat and sound. I will ``surf'' the spectrum to provide a sampling of what NDE has extracted past and present as well as try to couple to its future.

Ringermacher, Harry I.

2010-02-01

296

Computationally Efficient Approaches to Characterize the Dynamic Response of Microstructures Under Mechanical Shock  

Microsoft Academic Search

We present computationally efficient models and approaches to simulate the response of microstructures under mechanical shock. These approaches include a Galerkin-based reduced-order model and a hybrid approach utilizing the response of structures to static loads combined with the dynamic shock spectrum of a spring-mass-damper system. To demonstrate the accuracy and efficiency of these approaches, we apply them on cantilever and

Mohammad I. Younis; Daniel Jordy; James M. Pitarresi

2007-01-01

297

Improving incandescent bulb efficiency  

Microsoft Academic Search

Incandescent light bulb efficiency is improved by: (1) modifying the surface micro-structure of a lamp filament in such a way as to increase the emissivity in the visible region of the spectrum without significantly increasing this quantity outside this spectral region, or suppressing the emission of energy outside the visible portion of the spectrum by modifying the surface structure; (2)

Hauer

1980-01-01

298

Blackbody Spectrum Viewer  

NSDL National Science Digital Library

The blackbody calculator allows for visualization of the spectrum produced by objects of a given temperature. Users can see both a line graph of the spectrum and the spectrum as it would appear using a spectral grating, as well as the actual hot object.

Joiner, David; The Shodor Education Foundation, Inc.

299

FM video data link spectrum spreading  

NASA Astrophysics Data System (ADS)

A video data link system utilizes spread spectrum to decrease the susceptibility of a low power video link to radio frequency countermeasures. The video data link system utilizes a combination of spread spectrum direct-sequence modulation and frequency-hop along with frequency modulation to provide spectral spreading of radio frequency energy to a bandwidth much greater than the information bandwidth. The direct sequence modulation allows minimization of the number of frequency steps required for complete spectral filling of the operational bandwidth on an average basis. Frequency hop timing is determined from the phase of the direct sequence generator to simplify the frequency hop synchronization process in the receiver.

Holliday, Edward M.; Kirshtein, Phillip M.; Weathers, Glenn D.

1991-10-01

300

Structural aspects of molecular photoionization efficiency in micelles and vesicles as models for solar energy utilization. [N,N,N',N'-tetramethylbenzidine  

SciTech Connect

The structural aspects controlling charge separation in molecular photoionization reactions in organized molecular assemblies involving micelles and vesicles are being studied by optical and electron magnetic resonance techniques including the time domain technique of electron spin echo modulation (ESEM). Photoionization of N,N,N',N'-tetramethylbenzidine (TMB) to give the cation radical has been carried out in both liquid and frozen micellar and vesicular solutions. Cation-water interactions have been detected by ESEM analysis and indicate that the cation is localized asymmetrically within these organized molecular assemblies. Stearic acid nitroxide spin probes have also been used to determine that the neutral TMB molecule before photoionization is also localized asymmetrically within such organized molecular assemblies. Electron spin echo detection of laser photogenerated TMB cation in liquid micellar solutions gives a direct measurement of the phase memory magnetic relaxation time which gives additional structural information. The relationship of this structural data to the efficiency of photoionization in these systems is discussed.

Kevan, L.

1983-01-01

301

High-efficiency, one-step starch utilization by transformed Saccharomyces cells which secrete both yeast glucoamylase and mouse alpha-amylase.  

PubMed Central

Transformed, hybrid Saccharomyces strains capable of simultaneous secretion of glucoamylase and alpha-amylase have been produced. These strains could carry out direct, one-step assimilation of starch, with conversion efficiency greater than 93% during a 5-day growth period. One of the transformants converted 92.8% of available starch into reducing sugars in only 2 days. Glucoamylase secretion by these strains resulted from expression of one or more chromosomal STA genes derived from Saccharomyces diastaticus. The strains were transformed by a plasmid (pMS12) containing mouse salivary alpha-amylase cDNA in an expression vector containing yeast alcohol dehydrogenase promoter and a segment of yeast 2 micron plasmid. The major starch hydrolysis product produced by crude amylases found in culture broths was glucose, indicating that alpha-amylase and glucoamylase acted cooperatively.

Kim, K; Park, C S; Mattoon, J R

1988-01-01

302

High-efficiency, one-step starch utilization by transformed Saccharomyces cells which secrete both yeast glucoamylase and mouse alpha-amylase.  

PubMed

Transformed, hybrid Saccharomyces strains capable of simultaneous secretion of glucoamylase and alpha-amylase have been produced. These strains could carry out direct, one-step assimilation of starch, with conversion efficiency greater than 93% during a 5-day growth period. One of the transformants converted 92.8% of available starch into reducing sugars in only 2 days. Glucoamylase secretion by these strains resulted from expression of one or more chromosomal STA genes derived from Saccharomyces diastaticus. The strains were transformed by a plasmid (pMS12) containing mouse salivary alpha-amylase cDNA in an expression vector containing yeast alcohol dehydrogenase promoter and a segment of yeast 2 micron plasmid. The major starch hydrolysis product produced by crude amylases found in culture broths was glucose, indicating that alpha-amylase and glucoamylase acted cooperatively. PMID:3132104

Kim, K; Park, C S; Mattoon, J R

1988-04-01

303

Low-cost, high-efficiency solar cells utilizing GaAs-on-Si technology. Annual subcontract report, 1 August 1991--31 July 1992  

SciTech Connect

This report describes work to develop technology to deposit GaAs on Si using a nucleation layer of atomic-layer-epitaxy-grown GaAs or AlAs on Si. This ensures two-dimensional nucleation and should lead to fewer defects in the final GaAs layer. As an alternative, we also developed technology for depositing GaAs on sawtooth-patterned Si. Preliminary studies showed that this material can have a very low defect density, {approximately} 1 {times} 10{sup 5} cm{sup {minus}5}, as opposed to our conventionally grown GaAs on SL which has a typical defect density of over 1 {times}10{sup 7} cm{sup {minus}2}. Using these two now methods of GaAs-on-Si material growth, we made solar cells that are expected to show higher efficiencies than those of previous cells.

Vernon, S.M. [Spire Corp., Bedford, MA (United States)

1993-04-01

304

Cross-spectrum symbol synchronization  

NASA Technical Reports Server (NTRS)

A popular method of symbol synchronization exploits one aspect of generalized harmonic analysis, normally referred to as the cross-spectrum. Utilizing nonlinear techniques, the input symbol energy is effectively concentrated onto multiples of the symbol clock frequency, facilitating application of conventional phase lock synchronization techniques. A general treatment of the cross-spectrum technique is developed and shown to be applicable across a broad class of symbol modulation formats. An important specific symbol synchronization application is then treated, focusing the general development to provide both insight and quantitative measure of the performance impact associated with variation in these key synchronization parameters: symbol modulation format, symbol transition probability, symbol energy to noise density ratio, and symbol rate to filter bandwidth ratio.

Mccallister, R. D.; Simon, M. K.

1981-01-01

305

Improvement of Carbon Dioxide Sweep Efficiency by Utilization of Microbial Permeability Profile Modification to Reduce the Amount of Oil Bypassed During Carbon Dioxide Flood  

SciTech Connect

The objective of this project was to couple microbial permeability profile modification (MPPM), with carbon dioxide flooding to improve oil recovery from the Upper Cretaceous Little Creek Oil Field situated in Lincoln and Pike counties, MS. This study determined that MPPM technology, which improves production by utilizing environmentally friendly nutrient solutions to simulate the growth of the indigenous microflora in the most permeable zones of the reservoir thus diverting production to less permeable, previously unswept zones, increased oil production without interfering with the carbon dioxide flooding operation. Laboratory tests determined that no microorganisms were produced in formation waters, but were present in cores. Perhaps the single most significant contribution of this study is the demonstration that microorganisms are active at a formation temperature of 115?C (239?F) by using a specially designed culturing device. Laboratory tests were employed to simulate the MPPM process by demonstrating that microorganisms could be activated with the resulting production of oil in coreflood tests performed in the presence of carbon dioxide at 66?C (the highest temperature that could be employed in the coreflood facility). Geological assessment determined significant heterogeneity in the Eutaw Formation, and documented relatively thin, variably-lithified, well-laminated sandstone interbedded with heavily-bioturbated, clay-rich sandstone and shale. Live core samples of the Upper Cretaceous Eutaw Formation from the Heidelberg Field, MS were quantitatively assessed using SEM, and showed that during MPPM permeability modification occurs ubiquitously within pore and throat spaces of 10-20 ?m diameter. Testing of the MPPM procedure in the Little Creek Field showed a significant increase in production occurred in two of the five production test wells; furthermore, the decline curve in each of the production wells became noticeably less steep. This project greatly extends the number of oil fields in which MPPM can be implemented.

Darrel Schmitz; Lewis Brown F. Leo Lynch; Brenda Kirkland; Krystal Collins; William Funderburk

2010-12-31

306

Jerusalem artichoke powder: a useful material in producing high-optical-purity l-lactate using an efficient sugar-utilizing thermophilic Bacillus coagulans strain.  

PubMed

Jerusalem artichoke is a low-requirement crop, which does not interfere with food chain, and is a promising carbon source for industrial fermentation. Microbial conversion of such a renewable raw material to useful products, such as lactic acid, is an important objective in industrial biotechnology. In this study, high-optical-purity l-lactate was efficiently produced from the hydrolysates of Jerusalem artichoke powder by a thermophilic bacterium, Bacillus coagulans XZL4. High l-lactate production (134gl(-1)) was obtained using 267gl(-1) Jerusalem artichoke powder (total reducing sugars of 140gl(-1)) and 10gl(-1) of corn steep powder in fed-batch fermentation, with an average productivity of 2.5gl(-1)h(-1) and a yield of 0.96gg(-1) reducing sugars. The final product optical purity is 99%, which meets the requirement of lactic acid polymerization. Our study represents a cost-effective and promising method for polymer-grade l-lactate production using a cheap raw bio-resource. PMID:23306126

Wang, Limin; Xue, Zhangwei; Zhao, Bo; Yu, Bo; Xu, Ping; Ma, Yanhe

2013-02-01

307

Biomass utilization  

Microsoft Academic Search

Forty papers are presented in 6 sections: Biomass utilization - the concept; The raw material and its preparation; The structure and chemical composition of biomass; Conversion methods - biological; Conversion methods - thermochemical; and Engineering and economics in biomass utilization. Ten papers are of particular forestry interest: Forest inventories as the basis for a continuous monitoring of forest biomass resources

Coute

1983-01-01

308

Utility diversification  

SciTech Connect

After reviewing the pros and cons of public utility diversification, the author concludes that the balance of public interest is on the side of permitting public utility companies greater freedom to diversify than they now enjoy. He would eliminate the review of individual proposed investments outside of the public utility area on the grounds that regulators have no particular competence in this area. He would also eliminate the regulation of security issuances and dividend payments by the nonpublic utility entities. Regulation should see that the diversifying enterprise is structured and regulation of the utility entity so conducted as to insulate monoply ratepayers from risks as much as possible. This would limit regulation of the nonutility entity to seeing that the total size of the company's commitment to new diversification ventures does not threaten deterioration of the credit of the entire enterprise. 3 references.

Kahn, A.E.

1983-01-01

309

Optimization in spectrum-sliced optical networks  

NASA Astrophysics Data System (ADS)

Current communication in optical networks presents a wide range of granularities, making it hard to use the optical spectrum efficiently under the WDM framework. In Spectrum Sliced Optical Networks, the WDM rigid frequency grid is replaced by a more flexible structure, in which the spectrum is organized in frequency slots, and each traffic flow is assigned to an appropriate set of contiguous slots. The classical Routing and Wavelength Assignment (RWA) problem is then replaced by a Routing and Spectrum assignment (RSA) problem. This paper addresses an iterativa approach to balance the network load during the routing decision in Spectrum-Elastic Optical Path Networks. We have built numerical examples to illustrate the performance of our routing approach. Comparisons to other routing techniques show that our approach mitigates the lightpath requests blocking probability.

Day Rosario Assis, Karcius; Ferreira dos Santos, Alex; Almeida, Raul C.

2013-12-01

310

Residual feed intake as a feed efficiency selection tool and its relationship with feed intake, performance and nutrient utilization in Murrah buffalo calves.  

PubMed

Residual feed intake (RFI) is the difference between the actual and expected feed intake of an animal based on its body weight and growth rate over a specific period. The objective of this study was to determine the RFI of buffalo calves using residuals from appropriate linear regression models involving dry matter intake (DMI), average daily gain (ADG) and mid-test metabolic body weight. Eighteen male Murrah buffalo calves of 5-7 months were selected and fed individually. A feeding trial using ad libitum feeding of total mixed ration (TMR, concentrate/roughage = 40:60) was conducted for 52 days in which the daily DMI, weekly body weight (BW) and growth rate of the calves were monitored. RFI of calves ranged from -0.20 to +0.23 kg/day. Mean DMI (in grams per kilogram of BW(0.75)) during the feeding trial period was significantly (P < 0.05) lower in low RFI group (79.66 g/kg BW(0.75)) compared to high RFI (87.74 g/kg BW(0.75)). Average initial BW, final BW and mid-test BW(0.75) did not differ (P > 0.05) between low and high RFI groups. Over the course of a trial period, low RFI group animals consumed 10% less feed compared to high RFI group of animals, yet performed in a comparable manner in terms of growth rate. Metabolizable energy for maintenance (MEm) was found to be significantly (P < 0.05) lower in low RFI group (13.54 MJ/100 kg BW) as compared to that of high RFI group (15.56 MJ/100 kg BW). The present study indicates that RFI is a promising selection tool for the selection of buffaloes for increased feed efficiency. PMID:24563229

Subhashchandra Bose, Bisitha Kattiparambil; Kundu, Shivlal Singh; Tho, Nguyen Thi Be; Sharma, Vijay Kumar; Sontakke, Umesh Balaji

2014-04-01

311

Technology utilization program report  

NASA Technical Reports Server (NTRS)

The application of aerospace technology to the solution of public health and industrial problems is reported. Data cover: (1) development of an externally rechargeable cardiac pacemaker, (2) utilization of ferrofluids-colloidal suspensions of ferrite particles - in the efficient separation of nonferrous metals as Ni, Zn, Cu, and Al from shredded automobile scrap, and (3) development of a breathing system for fire fighters.

1974-01-01

312

Solar refrigeration utilizing zeolites  

Microsoft Academic Search

Zeolites offer a unique opportunity for a solid-gas adsorption refrigeration system because of their unusual sorption properties, in particular, extremely nonlinear adsorption isotherms. The operating principle of the zeolite system and experimental results are presented. The study demonstrates a zeolite system capable of providing refrigeration and ice production with very good engineering efficiency. This system utilizes natural zeolites as the

D. I. Tchernev

1979-01-01

313

Utility diversification  

SciTech Connect

A review of the available evidence of the effect of diversification on a utility's financial attractiveness suggests that diversified gas companies have higher earnings, better credit ratings, and more marketable securities than do the less diversified utilities. Regulatory commissions must, however, always be alert to ways in which a company's unregulated activities might adversely affect recipients of the regulated service. Once assured that the service customers are adequately protected, the commission should neither review the specific ventures of unregulated subsidiaries nor become involved in regulating their security issuances or dividend payments. In general, utility diversification should be subject only to managerial discretion and the discipline of the market.

Kahn, A.E.

1983-01-01

314

Utility diversification  

SciTech Connect

A review of the available evidence of the effect of diversification on a utility's financial attractiveness suggests that diversified gas companies have higher earnings, better credit ratings, and more marketable securities than do the less diversified utilities. Regulatory commissions must, however, always be alert to ways in which a company's unregulated activities might adversely affect consumers of the regulated service. Once assured that the service customers are adequately protected, the commission should neither review the specific ventures of unregulated subsidiaries nor become involved in regulating their security issuances or dividend payments. In general, utility diversification should be subject only to managerial discretion and the discipline of the market.

Kahn, A.E.

1982-01-01

315

Accelerating Spectrum Sharing Technologies  

SciTech Connect

Spectrum sharing potentially holds the promise of solving the emerging spectrum crisis. However, technology innovators face the conundrum of developing spectrum sharing technologies without the ability to experiment and test with real incumbent systems. Interference with operational incumbents can prevent critical services, and the cost of deploying and operating an incumbent system can be prohibitive. Thus, the lack of incumbent systems and frequency authorization for technology incubation and demonstration has stymied spectrum sharing research. To this end, industry, academia, and regulators all require a test facility for validating hypotheses and demonstrating functionality without affecting operational incumbent systems. This article proposes a four-phase program supported by our spectrum accountability architecture. We propose that our comprehensive experimentation and testing approach for technology incubation and demonstration will accelerate the development of spectrum sharing technologies.

Juan D. Deaton; Lynda L. Brighton; Rangam Subramanian; Hussein Moradi; Jose Loera

2013-09-01

316

Facial Feedback Mechanisms in Autistic Spectrum Disorders  

ERIC Educational Resources Information Center

Facial feedback mechanisms of adolescents with Autistic Spectrum Disorders (ASD) were investigated utilizing three studies. Facial expressions, which became activated via automatic (Studies 1 and 2) or intentional (Study 2) mimicry, or via holding a pen between the teeth (Study 3), influenced corresponding emotions for controls, while individuals…

Stel, Marielle; van den Heuvel, Claudia; Smeets, Raymond C.

2008-01-01

317

Increased Photovoltaic Power Output via Diffractive Spectrum Separation  

NASA Astrophysics Data System (ADS)

In this Letter, we report the preliminary demonstration of a new paradigm for photovoltaic power generation that utilizes a broadband diffractive-optical element (BDOE) to efficiently separate sunlight into laterally spaced spectral bands. These bands are then absorbed by single-junction photovoltaic cells, whose band gaps correspond to the incident spectral bands. We designed such BDOEs by utilizing a modified version of the direct-binary-search algorithm. Gray scale lithography was used to fabricate these multilevel optics. They were experimentally characterized with an overall optical efficiency of 70% over a wavelength range of 350-1100 nm, which was in excellent agreement with simulation predictions. Finally, two prototype devices were assembled: one with a pair of copper indium gallium selenide based photovoltaic devices, and another with GaAs and c-Si photovoltaic devices. These devices demonstrated an increase in output peak electrical power of ˜42% and ˜22%, respectively, under white-light illumination. Because of the optical versatility and manufacturability of the proposed BDOEs, the reported spectrum-splitting approach provides a new approach toward low-cost solar power.

Kim, Ganghun; Dominguez-Caballero, Jose A.; Lee, Howard; Friedman, Daniel J.; Menon, Rajesh

2013-03-01

318

The Electromagnetic Spectrum  

NSDL National Science Digital Library

This is a lesson about the electromagnetic spectrum. Learners will read two pages of information about the electromagnetic spectrum and answer questions in an accompanying worksheet. This activity is from the Stanford Solar Center's All About the Sun: Sun and Stars activity guide for Grades 5-8 and can also accompany the Stanford Solar Center's Build Your Own Spectroscope activity.

319

Sparticle spectrum constraints  

Microsoft Academic Search

The supersymmetric standard model with supergravity-inspired soft breaking terms predicts a rich spectrum of sparticles to be discovered at the SSC, LHC, and NLC. Because there are more supersymmetric particles than unknown parameters, one can write down sum rules relating their masses. We discuss the spectrum of sparticles from this point of view. Some of the sum rules do not

Stephen P. Martin; Pierre Ramond

1993-01-01

320

Fetal Alcohol Spectrum Disorder  

ERIC Educational Resources Information Center

Fetal alcohol spectrum disorder (FASD) is a serious and widespread problem in this country. Positioned within the community with links to children, families, and healthcare systems, school nurses are a critical element in the prevention and treatment of those affected by fetal alcohol spectrum disorder. Although most school nurses are familiar…

Caley, Linda M.; Kramer, Charlotte; Robinson, Luther K.

2005-01-01

321

Radiation detector spectrum simulator  

DOEpatents

A small battery operated nuclear spectrum simulator having a noise source generates pulses with a Gaussian distribution of amplitudes. A switched dc bias circuit cooperating therewith to generate several nominal amplitudes of such pulses and a spectral distribution of pulses that closely simulates the spectrum produced by a radiation source such as Americium 241.

Wolf, M.A.; Crowell, J.M.

1985-04-09

322

Pulse Interference Cancelling System for Spread Spectrum Signals.  

National Technical Information Service (NTIS)

Cancellation of pulse interference with no loss in the received level of the desired signal is obtained for a spread spectrum system which utilizes orthogonal multiplexed noise codes which when orthogonally multiplexed, matched-filter detected and linearl...

F. S. Gutleber

1982-01-01

323

Utility-Optimal Random-Access Control  

Microsoft Academic Search

This paper designs medium access control (MAC) protocols for wireless networks through the network utility maximization (NUM) framework. A network-wide utility max- imization problem is formulated, using a collision\\/persistence- probabilistic model and aligning selfish utility with total social welfare. By adjusting the parameters in the utility objective functions of the NUM problem, we can also control the tradeoff between efficiency

Jang-won Lee; Mung Chiang; A. Robert Calderbank

2007-01-01

324

Expert system for nuclide identification in gamma spectrum analysis  

Microsoft Academic Search

An expert system coupled with the gamma spectrum analysis system SAMPO has been developed for automating the qualitative identification of radionuclides as well as for determinating the quantitative parameters of the spectrum components. The program is written in C-language and runs in various environments ranging from PC's to UNIX workstations. The expert system utilizes a complete gamma library with over

P. A. Aarnio; J. J. Ala-Heikkilae; T. T. Hakulinen; J. T. Routti

1994-01-01

325

FFT and filter bank based spectrum sensing for WLAN signals  

Microsoft Academic Search

As wireless communication devices have increased rapidly, much attention has been paid to the spectrum resources. Cognitive Radio (CR) technology has received increasing attention as a potential approach to utilize more effectively the radio frequency bands. CRs need to dynamically and reliably determine spectral holes which could be used for secondary transmissions. In this study, wideband multichannel spectrum sensing techniques

Sener Dikmese; Markku Renfors; Hasan Dincer

2011-01-01

326

Matter power spectrum 101  

NASA Astrophysics Data System (ADS)

We modify the public PM code developed by Anatoly Klypin and Jon Holtzman to simulate cosmologies with arbitrary initial power spectrum and equation of state of dark energy. With this tool in hand, we perform the following studies on the matter power spectrum. With an artificial sharp peak at k ~ 0.2 h Mpc -1 in the initial power spectrum, we find that the position of the peak is not shifted by nonlinear evolution. An upper limit of the shift at the level of 0.02% is achieved by fitting the power spectrum local to the peak using a power law plus a Gaussian. This implies that, for any practical purpose, the baryon acoustic oscillation peaks in the matter power spectrum are not shifted by nonlinear evolution which would otherwise bias the cosmological distance estimation. We also find that the existence of a peak in the linear power spectrum would boost the nonlinear power at all scales evenly. This is contrary to what HKLM scaling relation predicts, but roughly consistent with that of halo model. We construct two dark energy models with the same linear power spectra today but different linear growth histories. We demonstrate that their nonlinear power spectra differ at the level of the maximum deviation of the corresponding linear power spectra in the past. Similarly, two constructed dark energy models with the same growth histories result in consistent nonlinear power spectra. This is hinting, not a proof, that linear power spectrum together with linear growth history uniquely determine the nonlinear power spectrum. Based on these results, we propose that linear growth history be included in the next generation fitting formulas of the nonlinear power spectrum. For simple dark energy models parametrized by w 0 and w a , the existing nonlinear power spectrum fitting formulas, which are calibrated for ACDM model, work reasonably well. The corrections needed are at percent level for the power spectrum and 10% level for the derivative of the power spectrum. We find that, for Peacock & Dodds (1996) fitting formula, the corrections to the derivative of the power spectrum are independent of w a but changing with redshift. As a short term solution, a fitting form could be developed for w 0 , w a models based on this fact.

Ma, Zhaoming

327

Clean and Efficient Utilization of Sewage Sludge  

SciTech Connect

This is the Final Report for the DOE SBIR Phase II project (Grant No. DE-FG03-98ER82573). This report summarizes accomplishments and results for the entire program. In this program an innovative technology has been devised for transforming sewage sludge into a high quality fuel and recovering its energy content. The technology being developed is generally applicable to nearly all municipal sewage sludge management facilities and coal-fired boilers. It will provide economic and environmental benefits.

Zamansky, Vladimir; Rizeq, George

2002-09-12

328

Statistical linearization based estimation of the peak response of nonlinear systems subject to the EC8 design spectrum  

SciTech Connect

A stochastic approach is proposed to obtain reliable estimates of the peak response of nonlinear systems to excitations specified via a response/design seismic spectrum. This is achieved without resorting to numerical integration of the governing nonlinear equations of motion. First, a numerical scheme is utilized to derive a power spectrum which is compatible in a stochastic sense to a given elastic design spectrum. This spectrum is then treated as the excitation spectrum in the context of the statistical linearization method to determine effective parameters, damping and stiffness, corresponding to an equivalent linear system (ELS). The obtained parameters are used in conjunction with the linear design spectrum, for various values of damping, to estimate the response of certain nonlinear systems. The case of single-degree-of-freedom systems with cubic stiffness nonlinearity and hysteretic systems whose restoring force traces a bilinear law are considered in conjunction with the elastic design spectrum prescribed by the European aseismic code provisions (EC8). Monte Carlo simulations pertaining to an ensemble of non-stationary EC 8 design spectrum compatible accelerograms are conducted to confirm that the average peak response of the nonlinear systems compare reasonably well with that of the ELS. This is true, even in cases where the response of the nonlinear oscillators deviates significantly from the linear one. In this manner, the proposed approach yields ELS which can reliably replace the original nonlinear systems in carrying out computationally efficient analyses in the initial stages of the aseismic design of structures under severe seismic excitations. Furthermore, the potential of this approach for developing inelastic design spectra from a given elastic design spectrum is established.

Spanos, Pol D. [L. B. Ryon Chair in Engineering, Rice University, MS 321, P.O. Box 1892, Houston, TX 77251 (United States); Giaralis, Agathoklis [Department of Civil and Environmental Engineering, Rice University, MS 318, P.O. Box 1892, Houston, TX 77251 (United States)

2008-07-08

329

Glary Utilities  

NSDL National Science Digital Library

Glary Utilities offers this free application to help users improve their system's performance and also protect their privacy. After installing the application, users can remove and back up faculty registry entries, along with offering a secure file deletion feature. This version is compatible with computers running Windows 98 and newer.

2008-01-01

330

Ash Utilization.  

National Technical Information Service (NTIS)

Contents: Production and utilization of ash in the United States; The inhibitory effect of fly ash with respect to the corrosion of steel in concretes; Fly ash concrete in buildings in Chicago; A review of ash specifications; Prediction of fly ash perform...

J. D. Spencer J. H. Faber N. H. Coates

1970-01-01

331

Axial mesodermal dysplasia spectrum.  

PubMed

We report on a 4-month-old boy with manifestations of both the oculo-auriculovertebral spectrum and the caudal regression sequence. He has preauricular appendages, thoracic and lumbar hemivertebrae, anomalies of the ribs, dextrocardia, sacral "dysplasia," dislocated hips, bilateral talipes equinovarus, imperforate anus, recto-vesical fistula, malformed scrotum, and undescended testes. As suggested by Russell et al. [1981], who reported a patient with similar anomalies, the spectrum of anomalies probably is due to a generalized alteration in mesodermal cell migration during the primitive streak period. The term "axial mesodermal dysplasia spectrum" best describes the widespread anomalies in the cranial and caudal regions. PMID:8465843

Stewart, F J; Nevin, N C; Brown, S

1993-02-15

332

The FCC Spectrum Auctions: An Early Assessment  

Microsoft Academic Search

This paper analyzes six spectrum auctions conducted by the Federal Communications Commission from July 1994 to May 1996. These auctions were simultaneous multiple-round auctions in which collections of licenses were auctioned simultaneously. This auction form proved remarkably successful. Similar items sold for similar prices, and bidders successfully formed efficient aggregations of licenses. Bidding behavior differed substantially in the auctions. The

Peter C. Cramton

1997-01-01

333

A Comprehensive Book on Autism Spectrum Disorders  

ERIC Educational Resources Information Center

The aim of the book is to serve for clinical, practical, basic and scholarly practices. In twentyfive chapters it covers the most important topics related to Autism Spectrum Disorders in the efficient way and aims to be useful for health professionals in training or clinicians seeking an update. Different people with autism can have very different…

Mohammadi, Mohammad-Reza, Ed.

2011-01-01

334

IRIS Spectrum Line Plot  

NASA Video Gallery

This video shows a line plot of the spectrum. The spectra here are shown for various locations on the Sun. The changes in the movie are caused by differing physical conditions in the locations. Cre...

335

The Visible Spectrum  

NSDL National Science Digital Library

This activity introduces learners to the visible portion of electromagnetic spectrum. A visible spectrum is projected in the classroom using a diffraction grating and learners reproduce it using colored pencils. Filters are also used to block portions of the spectrum. This activity is available on the back of the Electromagnetic Spectrum Poster which is a collaborative product of Astrophysics missions and staff comprising the Astrophysics SEPOF. The Astrophysics SEPOF is headquartered at the Space Telescope Science Institute, operated for NASA by the Association of Universities for Research in Astronomy (AURA). Request a paper copy of the poster from SEPOF through the "contact us" page of Amazing Space - be sure to include your mailing address.

336

The Electromagnetic Spectrum  

NSDL National Science Digital Library

This interactive, online module reviews the basics of the the electromagnetic spectrum and makes the connection between radiation theory and the images we get from weather satellites. Students will learn about: the electromagnetic spectrum; electromagnetic waves; the electromagnetic spectrum and radiation theory; and how satellite radiometers "see" different sections of the spectrum. The module is part of an online course for grades 7-12 in satellite meteorology, which includes 10 interactive modules. The site also includes lesson plans developed by teachers and links to related resources. Each module is designed to serve as a stand-alone lesson, however, a sequential approach is recommended. Designed to challenge students through the end of 12th grade, middle school teachers and students may choose to skim or skip a few sections.

337

Power spectrum with auxiliary fields in de Sitter space  

NASA Astrophysics Data System (ADS)

We use the auxiliary fields and (excited-) de Sitter solutions to study the standard power spectrum of primordial fluctuations of a scalar field in the early universe. The auxiliary fields are the negative norm solutions of the field equation and as is shown, with a fixed boundary condition, utilizing these states results in a finite power spectrum without any infinity. The power spectrum is determined by the de Sitter solutions up to some corrections and the space-time symmetry is not broken in this point of view. The modulation to the power spectrum is of order , where is the Hubble parameter and is the energy scale, e.g., the Planck scale.

Mohsenzadeh, M.; Tanhayi, M. R.; Yusofi, E.

2014-06-01

338

CREAM-MAC: Cognitive Radio-EnAbled MultiChannel MAC Protocol Over Dynamic Spectrum Access Networks  

Microsoft Academic Search

As the novel and effective approach to improving the utilization of the precious radio spectrum, cognitive radio technology is the key to realize the dynamic spectrum access (DSA) networks, where the secondary (unlicensed) users can opportunistically utilize the unused licensed spectrum in a way that confines the level of interference to the range the primary (licensed) users can tolerate. However,

Xi Zhang; Hang Su

2011-01-01

339

Gender Differences in Symptoms of Autism Spectrum Disorders in Toddlers  

ERIC Educational Resources Information Center

Gender differences in symptoms representing the triad of impairments of Autism Spectrum Disorders remain unclear. To date, the majority of research conducted on this topic has utilized samples of older children. Thus, the purpose of the current study was to utilize a sample of toddlers to investigate gender differences in symptom endorsements of…

Sipes, Megan; Matson, Johnny L.; Worley, Julie A.; Kozlowski, Alison M.

2011-01-01

340

Optical wireless applications: a solution to ease the wireless airwaves spectrum crunch  

NASA Astrophysics Data System (ADS)

Demands by the communications industry for greater and greater bandwidth push the capability of conventional wireless technology. Part of the Radio Spectrum that is suitable for mobility is very limited. Higher frequency waves above 30 GHz tend to travel only a few miles or less and generally do not penetrate solid materials very well. This offers a sustainable solution for the current Spectrum Crunch in the lower microwave bands. One mission of this paper is to demonstrate practical and usable networks that can select a self-limiting link distance, allowing spectrum reuse. The motivation for operators of such bands to actually choose to self-limit is that by doing so, they improve the signal-tonoise against competing users at a lower cost than trying to overcome interference. These characteristics of wave propagation are not necessarily disadvantageous as they enable more densely packed communications links. Thus, high frequencies can provide very efficient spectrum utilization through "selective spectrum reuse", and naturally increase the security of transmissions. Optical systems and networks offer a far greater bandwidth. This means new devices and systems have to be developed. Semiconductor Light Emitting Diode (LED) is considered to be the future primary lighting source for buildings, automobiles and aircrafts. LED provides higher energy efficiency compared to incandescent and fluorescent light sources and it will play a major role in the global reduction of carbon dioxide emissions, as a consequence of the significant energy savings. Lasers are also under investigation for similar applications. These core devices have the potential to revolutionize how we use light, including not only for illumination, but as well; for communications, sensing, navigation, positioning, surveillance, and imaging.

Kavehrad, M.

2013-01-01

341

The research of optical fiber Brillouin spectrum denoising based on wavelet transform and neural network  

NASA Astrophysics Data System (ADS)

The center frequency of Brillouin scattering spectrum is easily influenced by the noise and the measurement accuracy of optical fiber strain is reduced. So a novel denoising method which can be applied in the Brillouin scattering spectrum is developed in this article. The Brillouin scattering spectrum is decomposed into multi-scale detail coefficients and approximation coefficients by using the wavelet transform. The wavelet decomposition detail coefficients are threshold quantified by utilizing the threshold algorithm. At the same time, the wavelet decomposition approximation coefficients are trained and simulated by using the BP neural network in order to remove noise hided in the approximation coefficients. So the novel method can reduce the wavelet decomposition scales. The Brillouin scattering spectrum which has a better denoising effect can be gained by using the inverse wavelet transform, and the measurement accuracy of optical fiber strain is enhanced also. The results of simulation and experiment demonstrate that the proposed method can suppress noise better; accordingly, the new method can gain more precision optical fiber strain and reduce the wavelet decomposition scales effectively than the conventional wavelet denoising method. Theory analysis and experiment show that the method is reasonable and efficient.

Zhang, Zhi-hui; Hu, Wei-liang; Yan, Ji-song; Zhang, Peng

2013-08-01

342

Spectrum of wormholes  

SciTech Connect

Wormholes have been studied mainly in the semiclassical approximation as solutions of the classical Euclidean field equations. However, such solutions are rather special, and exist only for certain kinds of matter. On the other hand, one can represent wormholes in a more general manner as solutions of the Wheeler-DeWitt equation with appropriate boundary conditions. Minisuperspace models with massless minimal or conformal scalar fields have a discrete spectrum of these solutions. The Giddings-Strominger instanton solution corresponds to a sum of an infinite number of these solutions. Minisuperspace models with a massive scalar field also appear to have a discrete spectrum of such solutions, whose asymptotic form is given.

Hawking, S.W. (Institute for Theoretical Physics, University of California, Santa Barbara, CA (USA) Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Silver Street, Cambridge CB3 9EW (United Kingdom)); Page, D.N. (Institute for Theoretical Physics, University of California, Santa Barbara, CA (USA) Department of Physics, Pennsylvania State University, University Park, PA (USA) Theoretical Physics Institute, Department of Physics, University of Alberta, Edmonton, AB (Canada))

1990-10-15

343

NREL Spectrum of Innovation  

ScienceCinema

There are many voices calling for a future of abundant clean energy. The choices are difficult and the challenges daunting. How will we get there? The National Renewable Energy Laboratory integrates the entire spectrum of innovation including fundamental science, market relevant research, systems integration, testing and validation, commercialization and deployment. The innovation process at NREL is interdependent and iterative. Many scientific breakthroughs begin in our own laboratories, but new ideas and technologies come to NREL at any point along the innovation spectrum to be validated and refined for commercial use.

None

2013-05-29

344

NREL Spectrum of Innovation  

SciTech Connect

There are many voices calling for a future of abundant clean energy. The choices are difficult and the challenges daunting. How will we get there? The National Renewable Energy Laboratory integrates the entire spectrum of innovation including fundamental science, market relevant research, systems integration, testing and validation, commercialization and deployment. The innovation process at NREL is interdependent and iterative. Many scientific breakthroughs begin in our own laboratories, but new ideas and technologies come to NREL at any point along the innovation spectrum to be validated and refined for commercial use.

None

2011-01-01

345

Stellar Spectrum Synthesizer  

ERIC Educational Resources Information Center

Describes a device which employs two diffraction gratings and three or four simple lenses to produce arbitrary absorption or emission spectra that may be doppler shifted and spectroscopically examined by students some distance away. It may be regarded as a sort of artificial star whose spectrum may be analyzed as an undergraduate laboratory…

Landegren, G. F.

1975-01-01

346

Electromagnetic Spectrum Control Programs  

Microsoft Academic Search

The radio frequency spectrum is becoming increasingly saturated and polluted due to intensified use and unnecessary radiations and is being taxed severely to meet man's communications-electronics needs. Additional corrective measures are necessary-improved standards, increased concern for conservation of the resource, greater emphasis on intersystems compatibility, increased research, better educational and training programs, and the inclusion of economic and social values

Wilfred Dean

1971-01-01

347

Scaled angular spectrum method.  

PubMed

The angular spectrum method (ASM) calculates diffraction calculation in a high numerical aperture, unlike Fresnel diffraction. However, this method does not allow us to calculate at different sampling rates on source and destination planes. In this Letter, we propose a scaled ASM that calculates diffraction at different sampling rates on source and destination planes using the nonuniform fast Fourier transform. PMID:23027301

Shimobaba, Tomoyoshi; Matsushima, Kyoji; Kakue, Takashi; Masuda, Nobuyuki; Ito, Tomoyoshi

2012-10-01

348

Infrared Spectrum Shifter.  

National Technical Information Service (NTIS)

The work conducted on an infrared spectrum shifter, for the investigation of the feasibility of design of a high-power thermionic converter and for the development of infrared sources in the wavelength range 3 - 4 microns, is described. Main emphasis in t...

L. M. Vallese M. W. Wallace

1965-01-01

349

Fetal Alcohol Spectrum Disorders  

MedlinePLUS

... can cause a group of conditions called fetal alcohol spectrum disorders (FASDs).Effects can include physical and behavioral problems such as trouble with Learning and remembering Understanding and following ... as feeding and bathing Fetal alcohol syndrome is the most serious type of FASD. ...

350

The Frequency Spectrum Radio.  

ERIC Educational Resources Information Center

This journal issue focuses on the frequency spectrum used in radio communication and on the World Administrative Radio Conference, sponsored by the International Telecommunication Union, held in Geneva, Switzerland, in the fall of 1979. Articles describe the World Administrative Radio Conference as the most important radio communication conference…

Howkins, John, Ed.

1979-01-01

351

Eliminating Noise at the Box-fitting Spectrum  

NASA Astrophysics Data System (ADS)

Non gaussian sources of erros need to be taken into consideration when searching for planetary transits. Such phenomena are mostly caused by the impact of high energetic particles on the detector (Pinheiro da Silva et al. 2008). The detection efficiency of transits, therefor, depend significantly on the data quality and the algorithms utilized to deal with these errors sources. In this work we show that a modified detrend algorithm CDA (CoRoT Detrend Algorithm; Mislis et al. 2010) using a robust statistics and an empirical fit, instead of a polynomial one, can eliminate more efficiently gaps in the data and other long-term trends from the light-curve. Using this algorithm enables us to obtain a reconstructed light-curve with better signal-to-noise ratio that allows to improve the detection of exoplanet transits, although long term signals are destroyed. The results show that these modifications lead to an improved BLS (Box-fitting Least Squares; Kovács, Zucker & Mazeh 2002) algorithm spectrum. At the end we have compared our planetary search results with CoRoT (Convection, Rotation and planetary Transits) satellite chromatic light-curves available in the literature.

Boufleur, Rodrigo Carlos; Emilio, Marcelo; Pacheco, Eduardo Janot; de La Reza, Jorge Ramiro; da Rocha, José Carlos

2014-04-01

352

Network inefficiencies in autism spectrum disorder at 24 months.  

PubMed

Autism spectrum disorder (ASD) is a developmental disorder defined by behavioral symptoms that emerge during the first years of life. Associated with these symptoms are differences in the structure of a wide array of brain regions, and in the connectivity between these regions. However, the use of cohorts with large age variability and participants past the generally recognized age of onset of the defining behaviors means that many of the reported abnormalities may be a result of cascade effects of developmentally earlier deviations. This study assessed differences in connectivity in ASD at the age at which the defining behaviors first become clear. There were 113 24-month-old participants at high risk for ASD, 31 of whom were classified as ASD, and 23 typically developing 24-month-old participants at low risk for ASD. Utilizing diffusion data to obtain measures of the length and strength of connections between anatomical regions, we performed an analysis of network efficiency. Our results showed significantly decreased local and global efficiency over temporal, parietal and occipital lobes in high-risk infants classified as ASD, relative to both low- and high-risk infants not classified as ASD. The frontal lobes showed only a reduction in global efficiency in Broca's area. In addition, these same regions showed an inverse relation between efficiency and symptom severity across the high-risk infants. The results suggest delay or deficits in infants with ASD in the optimization of both local and global aspects of network structure in regions involved in processing auditory and visual stimuli, language and nonlinguistic social stimuli. PMID:24802306

Lewis, J D; Evans, A C; Pruett, J R; Botteron, K; Zwaigenbaum, L; Estes, A; Gerig, G; Collins, L; Kostopoulos, P; McKinstry, R; Dager, S; Paterson, S; Schultz, R T; Styner, M; Hazlett, H; Piven, J

2014-01-01

353

Network inefficiencies in autism spectrum disorder at 24 months  

PubMed Central

Autism spectrum disorder (ASD) is a developmental disorder defined by behavioral symptoms that emerge during the first years of life. Associated with these symptoms are differences in the structure of a wide array of brain regions, and in the connectivity between these regions. However, the use of cohorts with large age variability and participants past the generally recognized age of onset of the defining behaviors means that many of the reported abnormalities may be a result of cascade effects of developmentally earlier deviations. This study assessed differences in connectivity in ASD at the age at which the defining behaviors first become clear. There were 113 24-month-old participants at high risk for ASD, 31 of whom were classified as ASD, and 23 typically developing 24-month-old participants at low risk for ASD. Utilizing diffusion data to obtain measures of the length and strength of connections between anatomical regions, we performed an analysis of network efficiency. Our results showed significantly decreased local and global efficiency over temporal, parietal and occipital lobes in high-risk infants classified as ASD, relative to both low- and high-risk infants not classified as ASD. The frontal lobes showed only a reduction in global efficiency in Broca's area. In addition, these same regions showed an inverse relation between efficiency and symptom severity across the high-risk infants. The results suggest delay or deficits in infants with ASD in the optimization of both local and global aspects of network structure in regions involved in processing auditory and visual stimuli, language and nonlinguistic social stimuli.

Lewis, J D; Evans, A C; Pruett, J R; Botteron, K; Zwaigenbaum, L; Estes, A; Gerig, G; Collins, L; Kostopoulos, P; McKinstry, R; Dager, S; Paterson, S; Schultz, R T; Styner, M; Hazlett, H; Piven, J

2014-01-01

354

The spectrum of ?-ray burst: a clue  

NASA Astrophysics Data System (ADS)

In this work, we numerically calculate the thermal radiation efficiency of the baryonic outflow. The possible outflow acceleration in the transparent stage, which lowers thermal radiation efficiency, has been taken into account. In the standard internal shock model for the prompt emission, the fast shells should move with a typical Lorentz factor ~5 ?i otherwise the ?-ray burst (GRB) efficiency will be in disagreement with the observations, where ?i is the bulk Lorentz factor of the shocked/emitting region. The photosphere radius of these fast shells is small and the thermal radiation is too strong to be effectively outshone by the internal shock emission. This is particularly the case for some extremely bright events having ?i ~ 103, like GRBs 080319B and 080916C. The absence of a distinct thermal component in the spectrum of most GRBs challenges the standard internal shock model and may suggest a non-baryonic (magnetic) outflow component. Though the magnetic outflow model seems favoured by more and more data, it can hardly reproduce the typical GRB spectrum. In the photosphere-gradual magnetic dissipation scenario, the spectrum cuts off at ~1 GeV, too low to account for the observations of GRBs 080916C. In the sudden magnetic energy dissipation model, the low-energy spectrum is expected to be F? ~ ?-1/2, too soft to be consistent with the data F? ~ ?0. We speculate that the low-energy spectrum puzzle could be unveiled by the mechanism that particles, in the magnetic dissipation process, are repeatedly accelerated.

Fan, Yi-Zhong

2010-03-01

355

Efficient light harvesting by photon downconversion and light trapping in hybrid ZnS nanoparticles/Si nanotips solar cells.  

PubMed

A hybrid colloidal ZnS nanoparticles/Si nanotips p-n active layer has been demonstrated to have promising potential for efficient solar spectrum utilization in crystalline silicon-based solar cells. The hybrid solar cell shows an enhancement of 20% in the short-circuit current and approximately 10% in power conversion efficiency compared to its counterpart without integrating ZnS nanoparticles. The enhancement has been investigated by external quantum efficiency, photoluminescence excitation spectrum, photoluminescence, and reflectance to distinct the role of ZnS quantum dots for light harvesting. It is concluded that ZnS nanoparticles not only act as frequency downconversion centers in the ultraviolet region but also serve as antireflection coating for light trapping in the measured spectral regime. Our approach is ready to be extended to many other material systems for the creation of highly efficient photovoltaic devices. PMID:20873763

Huang, Chun-Ying; Wang, Di-Yan; Wang, Chun-Hsiung; Chen, Yung-Ting; Wang, Yaw-Tyng; Jiang, You-Ting; Yang, Ying-Jay; Chen, Chia-Chun; Chen, Yang-Fang

2010-10-26

356

The performance of water utilities in Jordan.  

PubMed

This paper aims to measure the relative performance of Jordan's water utilities for water sector (WS) and wastewater sector (WWS), and to investigate the major factors behind their inefficiencies. DEA (non-parametric method) and Tobit model (parametric method) were used at two stages. At the first stage DEA was used to evaluate the utilities' efficiency and to investigate the utilities' scale effect on efficiency. At the second stage Tobit model (regression) is applied to determine the impact of the non-controllable factors on utilities' inefficiencies where the efficiency score is the dependent variable in the regression. The results of DEA showed that there is a potential to reduce inputs level: water supply and operational expense (OPEX) for WS, and treated wastewater and OPEX for WWS, by around 15-20 and 23-27%, respectively. Aqaba and Jarash utilities are the most efficient utilities in the WS, while it is Amman utility in the WWS. The utility size has relatively moderate effect on the relative performance. It is concluded that the medium utility size for WS and large utility size for WWS is the most appropriate. Tobit model results indicate that commercialization activities have a clear positive impact on efficiency improvement for both sectors. PMID:20729581

Al-Assa'd, Tamer; Sauer, Johannes

2010-01-01

357

Evaluating Energy Conversion Efficiency  

NASA Technical Reports Server (NTRS)

Devices that convert solar radiation directly into storable chemical or electrical energy, have characteristic energy absorption spectrum; specifically, each of these devices has energy threshold. The conversion efficiency of generalized system that emcompasses all threshold devices is analyzed, resulting in family of curves for devices of various threshold energies operating at different temperatures.

Byvik, C. E.; Smith, B. T.; Buoncristiani, A. M.

1983-01-01

358

Time delay spectrum conditioner  

DOEpatents

A device for delaying specified frequencies of a multiple frequency laser beam. The device separates the multiple frequency beam into a series of spatially separated single frequency beams. The propagation distance of the single frequency beam is subsequently altered to provide the desired delay for each specific frequency. Focusing reflectors can be utilized to provide a simple but nonadjustable system or, flat reflectors with collimating and focusing optics can be utilized to provide an adjustable system.

Greiner, Norman R. (Los Alamos, NM)

1980-01-01

359

The Electromagnetic Spectrum  

NSDL National Science Digital Library

In this lesson, students are introduced to the electromagnetic spectrum. They observe a demonstration of the visible light spectrum created by a flashlight and a prism, complete an activity sheet where they identify the wavelength that is involved in technologies used in their communities, and learn about satellite sensors that remotely sense data. Student worksheets, a data sheet, answer keys, and Web links are included. This is Lesson 3 in Understanding Light, part of IMAGERS, Interactive Media Adventures for Grade School Education using Remote Sensing. The website provides hands-on activities in the classroom supporting the science content in two interactive media books, The Adventures of Echo the Bat and Amelia the Pigeon.

360

Exploring the Spectrum  

NSDL National Science Digital Library

This activity introduces students to the visible light spectrum, and demonstrates what happens to the appearance of an image when certain wavelengths of light are blocked by filters or made visible using special tools. Students are lead through experiments with light and filters, demonstrating that the broader the range of the electromagnetic spectrum we can detect, the more information we gather about the universe. By completing this activity, students gain background information that is necessary for activities that follow this one. This activity is part of the "Cosmic Questions: Our Place in Space and Time" educator's guide that was developed to support the Cosmic Questions exhibit. Activities in the guide can be used in conjunction with, or independently of, the exhibt.

361

Spread spectrum image steganography.  

PubMed

In this paper, we present a new method of digital steganography, entitled spread spectrum image steganography (SSIS). Steganography, which means "covered writing" in Greek, is the science of communicating in a hidden manner. Following a discussion of steganographic communication theory and review of existing techniques, the new method, SSIS, is introduced. This system hides and recovers a message of substantial length within digital imagery while maintaining the original image size and dynamic range. The hidden message can be recovered using appropriate keys without any knowledge of the original image. Image restoration, error-control coding, and techniques similar to spread spectrum are described, and the performance of the system is illustrated. A message embedded by this method can be in the form of text, imagery, or any other digital signal. Applications for such a data-hiding scheme include in-band captioning, covert communication, image tamperproofing, authentication, embedded control, and revision tracking. PMID:18267522

Marvel, L M; Boncelet, C R; Retter, C T

1999-01-01

362

Comparing welfare for spectrum property and spectrum commons governance regimes  

Microsoft Academic Search

The rapid growth of wireless communications has spurred a spirited debate over the advantages and disadvantages of alternative spectrum governance regimes. Of central concern are the merits of establishing full property rights in spectrum compared to organizing spectrum as an open commons. So far, this discussion has largely proceeded without a unifying framework within which claims and counterclaims can be

Carol Ting; Steven S. Wildman; Johannes M. Bauer

2005-01-01

363

Spectrum tailoring of the neutron energy spectrum in the context of delayed neutron detection  

SciTech Connect

For the purpose of measuring plutonium mass in spent fuel, a delayed neutron instrument is of particular interest since, if properly designed, the delayed neutron signal from {sup 235}U is significantly stronger than the signature from {sup 239}Pu or {sup 241}Pu. A key factor in properly designing a delayed neutron instrument is to minimize the fission of {sup 238}U. This minimization is achieved by keeping the interrogating neutron spectrum below {approx} 1 MeV. In the context of spent fuel measurements it is desirable to use a 14 MeV (deuterium and tritium) neutron generator for economic reasons. Spectrum tailoring is the term used to describe the inclusion of material between the 14 MeV neutrons and the interrogated object that lower the neutron energy through nuclear reactions and moderation. This report quantifies the utility of different material combination for spectrum tailoring.

Koehler, William E [Los Alamos National Laboratory; Tobin, Steve J [Los Alamos National Laboratory; Sandoval, Nathan P [Los Alamos National Laboratory; Fensin, Mike L [Los Alamos National Laboratory

2010-01-01

364

Exploiting Heterogeneity Wireless Channels for Opportunistic Routing in Dynamic Spectrum Access Networks  

Microsoft Academic Search

In this paper, we exploit the heterogeneity of wire- less channels and propose an efficient opportunistic cognitive routing (OCR) scheme for dynamic spectrum access (DSA) networks. We first introduce a novel routing metric by jointly considering physical characteristics of spectrum bands and di- verse activities of primary users (PU) in each band. To effectively explore the spectrum opportunities, a proper

Yongkang Liu; Lin X. Cai; Xuemin Shen; Jon W. Mark

2011-01-01

365

Wavelet basis spectrum recovery for nonuniformly sampled interferogram  

NASA Astrophysics Data System (ADS)

Interferogram obtained by Temporally-Spatially Modulated Fourier Transform Spectrometers should be recovered to spectrum by fast Fourier transform method (FFT). However, the interferogram sometimes is nonuniformly sampled, which cannot use FFT directly. In this paper, we propose a wavelet basis fitting method to interpolate the interferogram onto an equal-spaced grid. Hence, we can utilize FFT to recover spectrum. The simulated result of the recovered spectrum indicates that the proposed interferogram wavelet basis fitting method can interpolate the nonuniformly sampled interferogram effectively. The preliminary results show that this method introduces less errors than the Polynomial fitting method does.

Ding, Xiaoming; Yuan, Yan; Su, Lijuan; Huang, Fengzhen

2013-12-01

366

The cleanest Fourier spectrum  

NASA Astrophysics Data System (ADS)

A new method of removing false peaks from a power spectrum is introduced, the CLEANest algorithm, together with several variations on the theme. It is shown to be an effective technique for detecting and describing multiperiodic signals, and at least in some cases is capable of divining the true nature of a multiperiodic signal, even when the single strongest peak in a periodogram occurs at a spurious frequency. The method is capable of describing long-term time evolution of period and amplitude. These techniques are applied to artificial test data, and to visual observations of variable stars from the International Database of the American Association of Variable Star Observers (AAVSO).

Foster, Grant

1995-04-01

367

Electric utilities in 2007  

SciTech Connect

A century ago--in the year J.J. Thomson discovered the electron--electricity, gas and traction companies battled for markets, and corrupt city councils demanded their fair share of the take. One tycoon became so disgusted with the confusion and dishonesty that he decided to bribe the legislature to set up an honest, state-run regulatory agency that would bring order to chaos. But he was found out. The scandal set back the cause of regulation until 1907, the year in which the electric washing machine and the vacuum cleaner were invented. By then, electricity sales had septupled from 1897 levels, and three states had established utility regulation. In the coming decade, 1997 to 2007, the utility business could undergo similar dramatic change, but it will move toward less regulation and more competition during a period of slow growth. Management will have to work harder to achieve success, however, because much of the profits will have to come not from a growing market but from the pockets of competitors. By 2007, electricity will constitute a component of a larger energy and utility services industry that sells electricity, natural gas and possibly water, propane and telecommunications. Customized service will meet the needs of consumers of all sizes. The dominant firm in the industry, the virtual utility, may look more like a financial organization or a mass marketer than the traditional converter of raw material to energy. Emphasis on market-based pricing should lead to more efficient use of resources. If the process works right, the consumer wins.

Hyman, L.S. [Smith Barney Inc., New York, NY (United States)

1998-10-01

368

Resource utilization during software development  

NASA Technical Reports Server (NTRS)

This paper discusses resource utilization over the life cycle of software development and discusses the role that the current 'waterfall' model plays in the actual software life cycle. Software production in the NASA environment was analyzed to measure these differences. The data from 13 different projects were collected by the Software Engineering Laboratory at NASA Goddard Space Flight Center and analyzed for similarities and differences. The results indicate that the waterfall model is not very realistic in practice, and that as technology introduces further perturbations to this model with concepts like executable specifications, rapid prototyping, and wide-spectrum languages, we need to modify our model of this process.

Zelkowitz, Marvin V.

1988-01-01

369

Spectrum of physics comprehension  

NASA Astrophysics Data System (ADS)

The paper presents the results of research on the relationship between self-assessed comprehension of physics lectures and final grades of junior high school students (aged 13-15), high school students (aged 16-18) and physics students at the Pedagogical University of Cracow, Poland (aged 21). Students' declared level of comprehension was measured during a physics lecture on a prearranged scale of 1-10 with the use of a personal response system designed for the purpose of this experiment. Through the use of this tool, we obtained about 2000 computer records of students' declared comprehension of a 45 min lecture, which we named ‘the spectrum of comprehension’. In this paper, we present and analyse the correlation between students' declared comprehension of the content presented in the lecture and their final learning results.

Blasiak, W.; Godlewska, M.; Rosiek, R.; Wcislo, D.

2012-05-01

370

Microwave Spectrum of Hexafluoroisopropanol  

NASA Astrophysics Data System (ADS)

Hexafluoroisopropanol (HFIP) is an important organic solvent and probably the only solvent which can dissolve polythene. IR studies, on this molecule confirm the existence of antiperiplanar (ap) and synclinical (sc) conformers. We have observed pure rotational spectrum of this molecule and the fitted rotational constants (A= 2105.1208(11) MHz, B= 1053.9942(3) MHz, C= 932.3398(3) MHz) confirm the presence of ap conformer. There are many other observed lines which most probably corresponds to sc structure and due to the large amplitude motion of H-atom, some of these transitions show tunneling splitting. Work is in progress for the deuterated (OD) and C-13 isotopologues of the monomer. HFIP is expected to exhibit interesting hydrogen bonding properties and we are planning to investigate them by studying its complex with water. The results will be presented in this talk. H. Schaal, T. Höber, and M. A. Suhm, J. Phys. Chem. A 104, 265 (2000).

Shahi, Abhishek; Mani, Devendra; Arunan, E.

2012-06-01

371

Rotational spectrum of tryptophan  

NASA Astrophysics Data System (ADS)

The rotational spectrum of the natural amino acid tryptophan has been observed for the first time using a combination of laser ablation, molecular beams, and Fourier transform microwave spectroscopy. Independent analysis of the rotational spectra of individual conformers has conducted to a definitive identification of two different conformers of tryptophan, with one of the observed conformers never reported before. The analysis of the 14N nuclear quadrupole coupling constants is of particular significance since it allows discrimination between structures, thus providing structural information on the orientation of the amino group. Both observed conformers are stabilized by an O-H...N hydrogen bond in the side chain and a N-H...? interaction forming a chain that reinforce the strength of hydrogen bonds through cooperative effects.

Sanz, M. Eugenia; Cabezas, Carlos; Mata, Santiago; Alonso, Josè L.

2014-05-01

372

Rotational spectrum of tryptophan.  

PubMed

The rotational spectrum of the natural amino acid tryptophan has been observed for the first time using a combination of laser ablation, molecular beams, and Fourier transform microwave spectroscopy. Independent analysis of the rotational spectra of individual conformers has conducted to a definitive identification of two different conformers of tryptophan, with one of the observed conformers never reported before. The analysis of the (14)N nuclear quadrupole coupling constants is of particular significance since it allows discrimination between structures, thus providing structural information on the orientation of the amino group. Both observed conformers are stabilized by an O-H···N hydrogen bond in the side chain and a N-H···? interaction forming a chain that reinforce the strength of hydrogen bonds through cooperative effects. PMID:24880281

Sanz, M Eugenia; Cabezas, Carlos; Mata, Santiago; Alonso, Josè L

2014-05-28

373

Fetal Alcohol Spectrum Disorders  

PubMed Central

Forty years ago, alcohol was not commonly recognized as a teratogen, an agent that can disrupt the development of a fetus. Today, we understand that prenatal alcohol exposure induces a variety of adverse effects on physical, neurological, and behavioral development. Research supported by the National Institute on Alcohol Abuse and Alcoholism (NIAAA) has contributed to the identification of the range and prevalence of fetal alcohol spectrum disorders (FASD), as well as methods for prevention and treatment of FASD. The worldwide prevalence and high personal and societal costs of FASD speak to the importance of this research. This article briefly examines some of the ways that NIAAA has contributed to our understanding of FASD, the challenges that we still face, and how this research is translated into changes in public policy.

Thomas, Jennifer D.; Warren, Kenneth R.; Hewitt, Brenda G.

2010-01-01

374

Autism spectrum disorders  

PubMed Central

Pervasive developmental disorders are a group of neurodevelopmental disorders characterized by impairments in communication, reciprocal social interaction and restricted repetitive behaviors or interests. The term autism spectrum disorders (ASD) has been used to describe their variable presentation. Although the cause of these disorders is not yet known, studies strongly suggest a genetic basis with a complex mode of inheritance. More research is needed to explore environmental factors that could be contributing to the cause of these disorders. The occurrence of ASD has been increasing worldwide, with the most recent prevalence studies indicating that they are present in 6 per 1000 children. The objectives of this article are to provide physicians with relevant information needed to identify and refer children presenting with symptoms suggestive of ASDs to specialized centers early, and to make them feel comfortable in dealing with public concerns regarding controversial issues about the etiology and management of these disorders.

Faras, Hadeel; Al Ateeqi, Nahed; Tidmarsh, Lee

2010-01-01

375

Spectrum of Magnetohydrodynamic Turbulence  

NASA Astrophysics Data System (ADS)

We propose a phenomenological theory of strong incompressible magnetohydrodynamic turbulence in the presence of a strong large-scale external magnetic field. We argue that in the inertial range of scales, magnetic-field and velocity-field fluctuations tend to align the directions of their polarizations. However, the perfect alignment cannot be reached; it is precluded by the presence of a constant energy flux over scales. As a consequence, the directions of shear-Alfvén fluid and magnetic-field fluctuations at each scale ? become effectively aligned within the angle ????1/4, which leads to scale-dependent depletion of the nonlinear interaction and to the field-perpendicular energy spectrum E(k?)?k?-3/2. Our results may be universal, i.e., independent of the external magnetic field, since small-scale fluctuations locally experience a strong field produced by large-scale eddies.

Boldyrev, Stanislav

2006-03-01

376

The OT Spectrum Management Support Program-An Overview  

Microsoft Academic Search

This paper gives an overview of the Office of Telecommunications, U. S. Department of Commerce, spectrum management support program. The program includes day-to-day operations concerned with providing frequency assignments to qualified U. S. federal government users, as well as planning and analysis support to help ensure efficient use of the radio spectrum from a long-term viewpoint. The program elements include:

Stanley Chon

1977-01-01

377

Comparative study of ocean wave spectrum using ENVISAT SAR data and wave rider buoy data  

NASA Astrophysics Data System (ADS)

A comparative study of ENVISAT ASAR data and corresponding wave rider buoy data has been attempted. An algorithm has been developed to retrieve Ocean Wave Spectrum from SAR data. The resulting spectrum is compared with the wave rider buoy measured wave spectrum. To compute the 2-D image spectrum from multi-look SAR data, various corrections to the original SAR data has been applied. Thereafter, Modulation Transfer Function has been computed and utilized to convert image spectrum to the Ocean Wave Spectrum. This final ocean wave height spectrum is used to estimate the ocean wave spectral parameters and has been compared with the in-situ measurements and model derived wave spectrum. An attempt has also been made to process the Single Look Complex (SLC) data to reduce the speckle noise in the SAR data using Fast Fourier Transform (FFT).

Jagadeesha Pai, B.; Kumar, Raj; Sarkar, Abhijit; Hegde, A. Vittal; Dwarakish, G. S.

2006-12-01

378

Analysis of neutron spectrum effects on primary damage in tritium breeding blankets  

NASA Astrophysics Data System (ADS)

The effect of neutron spectrum on primary damages in a structural material of a tritium breeding blanket is investigated with a newly established recoil spectrum estimation system. First, a recoil spectrum generation code is developed to obtain the energy spectrum of primary knock-on atoms (PKAs) for a given neutron spectrum utilizing the latest ENDF/B data. Secondly, a method for approximating the high energy tail of the recoil spectrum is introduced to avoid expensive molecular dynamics calculations for high energy PKAs using the concept of recoil energy of the secondary knock-on atoms originated by the INtegration of CAScades (INCAS) model. Thirdly, the modified spectrum is combined with a set of molecular dynamics calculation results to estimate the primary damage parameters such as the number of surviving point defects. Finally, the neutron spectrum is varied by changing the material of the spectral shifter and the result in primary damage parameters is examined.

Choi, Yong Hee; Joo, Han Gyu

2012-07-01

379

Conservation and renewable energy technologies for utilities  

SciTech Connect

This publication presents current efforts by the US DOE Office of Utility Technologies to promote and develop cost-effective renewable energy and energy efficient technologies in the Utility sector. Major projects in the areas of solar thermal energy, solar photovoltaic energy, wind energy, geothermal energy, hydroelectric power, ocean power, and biomass are presented. The importance of efficient energy management in the transmission and distribution of electricity and through energy storage is discussed. (GHH)

Not Available

1992-04-01

380

Early Onset Bipolar Spectrum Disorder: Psychopharmacological, Psychological, and Educational Management  

ERIC Educational Resources Information Center

Although published research continues to advocate medication as the first line of treatment for early onset bipolar spectrum disorder (EOBSD; N. Lofthouse & M.A. Fristad, 2004), preliminary research demonstrating the utility of cognitive, cognitive-behavioral, and psychoeducational therapies is promising. It appears as if future treatment of EOBSD…

McIntosh, David E.; Trotter, Jeffrey S.

2006-01-01

381

Emission Spectrum of Nitric Oxide in the Near Infrared.  

National Technical Information Service (NTIS)

The nitric oxide emission spectrum of the vibrationrotation bands of the electronic ground state has been observed in the 1.83-195 micron and 2.63-2.81 micron regions. A high tension discharge through NO at reduced pressure was utilized as the source. The...

E. F. Horn

1964-01-01

382

Implementation Science, Professional Development, and Autism Spectrum Disorders  

ERIC Educational Resources Information Center

The increased prevalence of autism spectrum disorders (ASD) has intensified the need for high-quality special education services designed for children and youth with ASD and their families. Implementation science provides guidance for moving innovation, such as utilizing evidence- based practices for students with ASD, into regular practice in…

Odom, Samuel L.; Cox, Ann W.; Brock, Matthew E.

2013-01-01

383

Pressure Spectrum in Homogeneous Turbulence  

NASA Astrophysics Data System (ADS)

The pressure spectrum in homogeneous steady turbulence is studied using direct numerical simulation with resolution up to 10243 and the Reynolds number R? between 38 and 478. The energy spectrum is found to have a finite inertial range with the Kolmogorov constant K = 1.65+/-0.05 followed by a bump at large wave numbers. The pressure spectrum in the inertial range is found to be approximately P\\(k\\) = Bp?¯4/3k-7/3 with Bp = 8.0+/-0.5, and followed by a bump of nearly k-5/3 at higher wave numbers. Universality and a new scaling of the pressure spectrum are discussed.

Gotoh, Toshiyuki; Fukayama, Daigen

2001-04-01

384

Supporting Dynamic Spectrum Access in Heterogeneous LTE+ Networks  

SciTech Connect

As early as 2014, mobile network operators’ spectral capac- ity is expected to be overwhelmed by the demand brought on by new devices and applications. With Long Term Evo- lution Advanced (LTE+) networks likely as the future one world 4G standard, network operators may need to deploy a Dynamic Spectrum Access (DSA) overlay in Heterogeneous Networks (HetNets) to extend coverage, increase spectrum efficiency, and increase the capacity of these networks. In this paper, we propose three new management frameworks for DSA in an LTE+ HetNet: Spectrum Accountability Client, Cell Spectrum Management, and Domain Spectrum Man- agement. For these spectrum management frameworks, we define protocol interfaces and operational signaling scenar- ios to support cooperative sensing, spectrum lease manage- ment, and alarm scenarios for rule adjustment. We also quan- tify, through integer programs, the benefits of using DSA in an LTE+ HetNet, that can opportunistically reuse vacant TV and GSM spectrum. Using integer programs, we consider a topology using Geographic Information System data from the Blacksburg, VA metro area to assess the realistic benefits of DSA in an LTE+ HetNet.

Luiz A. DaSilva; Ryan E. Irwin; Mike Benonis

2012-08-01

385

Improved motors for utility applications. Final report  

Microsoft Academic Search

The objective of EPRI RP-1763 Improved Motors for Utility Applications, is to evaluate the reliability and performance of present powerhouse motors and to identify design and operational characteristics which, through advanced development, offer the potential of increased reliability, performance, and efficiency. The initial activity of this project was an Industry Assessment Study to develop a data base of utility motor

E. P. Cornell; E. L. Owen; J. C. Appiarius; R. M. McCoy; P. F. Albrecht; D. W. Houghtaling

1982-01-01

386

California Public Utilities Commission conservation programs  

Microsoft Academic Search

California utilities traditionally subsidized the extension of service lines to new homes until they became aware that this practice encouraged waste and inefficiency. A new credit system was designed to reward builders of energy-efficient homes, especially those which require a minimum of summer air conditioning. Utilities have started programs to help planners and local governments modify building codes to take

Clinton

2009-01-01

387

SPECTRUM V--INFINITE MEDIUM THERMAL FLUX SPECTRUM PROGRAM  

Microsoft Academic Search

Program Spectrum is described for use in calculating the thermal neutron ; flux spectrum in an infinite homogeneous medium using scattering kernels for ; monatomic heavy gas with a Maxwellian distribution of velocities. Input ; parameters necessary for the calculation are the temperature, atomic mass of the ; moderator, cross sections and atomlc densities of moderator and absorbers, energy ;

Schlosser

1961-01-01

388

40 CFR 74.44 - Reduced utilization for combustion sources.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Reduced utilization for combustion sources. 74.44 Section...Compliance § 74.44 Reduced utilization for combustion sources. (a) Calculation...input + Reduction from improved efficiency where,...

2010-07-01

389

40 CFR 74.44 - Reduced utilization for combustion sources.  

Code of Federal Regulations, 2010 CFR

...2009-07-01 false Reduced utilization for combustion sources. 74.44 Section...Compliance § 74.44 Reduced utilization for combustion sources. (a) Calculation...input + Reduction from improved efficiency where,...

2009-07-01

390

PINS Spectrum Identification Guide  

SciTech Connect

The Portable Isotopic Neutron Spectroscopy—PINS, for short—system identifies the chemicals inside munitions and containers without opening them, a decided safety advantage if the fill chemical is a hazardous substance like a chemical warfare agent or an explosive. The PINS Spectrum Identification Guide is intended as a reference for technical professionals responsible for the interpretation of PINS gamma-ray spectra. The guide is divided into two parts. The three chapters that constitute Part I cover the science and technology of PINS. Neutron activation analysis is the focus of Chapter 1. Chapter 2 explores PINS hardware, software, and related operational issues. Gamma-ray spectral analysis basics are introduced in Chapter 3. The six chapters of Part II cover the identification of PINS spectra in detail. Like the PINS decision tree logic, these chapters are organized by chemical element: phosphorus-based chemicals, chlorine-based chemicals, etc. These descriptions of hazardous, toxic, and/or explosive chemicals conclude with a chapter on the identification of the inert chemicals, e.g. sand, used to fill practice munitions.

A.J. Caffrey

2012-03-01

391

Fetal Alcohol Spectrum Disorders  

PubMed Central

The adverse effects of prenatal alcohol consumption have long been known; however, a formal description and clinical diagnosis of these effects was not introduced until 1973. Since then, the distinction of the wide range of effects that can be induced by prenatal alcohol exposure, and, consequently, the terminology to describe these effects has continued to evolve. Although much progress has been made in understanding the consequences of prenatal alcohol exposure, challenges still remain in properly identifying all affected individuals as well as their individual patterns of alcohol-induced deficits. Also, as the large numbers of women who continue to drink during pregnancy indicate, prevention efforts still require further refinement to enhance their effectiveness. In addition, the mechanisms underlying alcohol-induced damage have not yet been fully elucidated; as knowledge of the mechanisms underlying alcohol-induced deficits continues to grow, the possibility of minimizing potential harm by intervening during prenatal alcohol exposure is enhanced. Finally, researchers are exploring additional ways to improve or fully restore behavioral and cognitive functions disrupted by prenatal alcohol exposure by treating the individuals with fetal alcohol spectrum disorders, thereby reducing the heavy burden for affected individuals and their families.

Warren, Kenneth R.; Hewitt, Brenda G.; Thomas, Jennifer D.

2011-01-01

392

Neuromyelitis optica spectrum disorders.  

PubMed

Since the discovery of aquaporin 4-IgG, a sensitive and highly specific biomarker of neuromyelitis optica (NMO), a wide range of syndromes have been recognized as being associated with this condition. This observation has led to new proposed terminology for the entire disorder, NMO spectrum disorders (NMOSD). The discovery of a pathogenic autoantibody and its target antigen has also facilitated basic research into the immunopathogenesis of the disease. Key advances include establishment of passive transfer animal models demonstrating the pathogenic potential of the autoantibody and confirming an important role of complement suggested by immunopathology of NMO brain lesions and of B-cell subsets, plasmablasts in particular. These discoveries have led to phase 1 clinical trials of targeted immunotherapy with potential for improved efficacy and less toxicity than current empiric immunosuppressant medications used to treat NMOSD. Randomized clinical trials are beginning to assess the efficacy and safety of a variety of immunotherapies in NMOSD. Therapeutic options are likely to increase, and improved outcomes in NMOSD patients are anticipated. PMID:25027264

Flanagan, Eoin P; Weinshenker, Brian G

2014-09-01

393

Describing Research Informed Consent in Persons with Schizophrenia Spectrum Disorders (SSDs): Responses and Correlates  

PubMed Central

This manuscript describes the responses and correlates of outpatients with schizophrenia spectrum disorders to a tool designed to measure comprehension before obtaining informed consent for research participation. We used the Evaluation to Sign Consent (ESC) Form to document comprehension in 100 outpatients as part of their consent to participate in a study of an exercise intervention. The exercise intervention study is ongoing; these findings suggest that the ESC is a feasible and acceptable approach for documenting comprehension of research procedures prior to obtaining informed consent. Age 49 years and older and the receipt of intramuscular antipsychotic medication predicted the need for additional assistance to successfully complete the ESC (?2 = 8.29, p = 0.016). Nurse researchers should consider documenting comprehension with the ESC due to its availability, time efficiency and utility.

Beebe, Lora Humphrey; Smith, Kathlene

2010-01-01

394

50 CFR 600.330 - National Standard 5-Efficiency.  

Code of Federal Regulations, 2013 CFR

...as its sole purpose. (b) Efficiency in the utilization of resources...practicable or desirable. (2) Efficiency. In theory, an efficient...labor, capital, interest, and fuel. Efficiency in terms of aggregate costs...

2013-10-01

395

Information and image integration: project spectrum  

NASA Astrophysics Data System (ADS)

The BJC Health System (BJC) and the Washington University School of Medicine (WUSM) formed a technology alliance with industry collaborators to develop and implement an integrated, advanced clinical information system. The industry collaborators include IBM, Kodak, SBC and Motorola. The activity, called Project Spectrum, provides an integrated clinical repository for the multiple hospital facilities of the BJC. The BJC System consists of 12 acute care hospitals serving over one million patients in Missouri and Illinois. An interface engine manages transactions from each of the hospital information systems, lab systems and radiology information systems. Data is normalized to provide a consistent view for the primary care physician. Access to the clinical repository is supported by web-based server/browser technology which delivers patient data to the physician's desktop. An HL7 based messaging system coordinates the acquisition and management of radiological image data and sends image keys to the clinical data repository. Access to the clinical chart browser currently provides radiology reports, laboratory data, vital signs and transcribed medical reports. A chart metaphor provides tabs for the selection of the clinical record for review. Activation of the radiology tab facilitates a standardized view of radiology reports and provides an icon used to initiate retrieval of available radiology images. The selection of the image icon spawns an image browser plug-in and utilizes the image key from the clinical repository to access the image server for the requested image data. The Spectrum system is collecting clinical data from five hospital systems and imaging data from two hospitals. Domain specific radiology imaging systems support the acquisition and primary interpretation of radiology exams. The spectrum clinical workstations are deployed to over 200 sites utilizing local area networks and ISDN connectivity.

Blaine, G. James; Jost, R. Gilbert; Martin, Lori; Weiss, David A.; Lehmann, Ron; Fritz, Kevin

1998-07-01

396

Asynchronous spread spectrum communication paradigm for use in low-power applications: description and simulation results  

NASA Astrophysics Data System (ADS)

Contemporary wireless communication strategies focus on efficient use of bandwidth in order to allow more users to exploit the RF spectrum through techniques like Frequency-hopping spread spectrum (SS) and Direct-sequence SS. In many real-world applications, these methods are implemented for synchronous communication systems. To achieve synchronous communication, two-way handshaking that requires overhead circuitry is performed between the sender and receiver. In order to use spread spectrum methods for certain unconstrained and low-power applications, such as implantable and remote monitoring devices, it is necessary to refine these methods to support asynchronous communication. We have designed and modeled a SS system, which could be integrated with a custom integrated circuit that would provide elementary multi-user communication. The SS logic generates a gold-code based on address and data bits that is then modulated with a carrier to transmit the information. Because the system is asynchronous, we treat each transmitted code as an independent piece of information. The receiver decodes the information using a full correlation with the ideal known gold-codes. For efficiency purposes, the filter is applied in the frequency domain. A threshold is applied to the output of the filter to determine if a particular code is transmitted as well as the point in time/space from which the signal was sent. The method was simulated and evaluated under several scenarios including different carrier frequencies, multiple targets, and various positions relative to the receiver from the simulated receiver. The results demonstrate the utility of asynchronous SS under many different conditions.

Welch, E. B.; Holmes, David R., III; Coker, Jonathan D.; Schaefer, Timothy M.; Gilbert, Barry K.; Daniel, Erik S.

2005-06-01

397

Tribal Utility Feasibility Study  

SciTech Connect

The Schatz Energy Research Center (SERC) assisted the Yurok Tribe in investigating the feasibility of creating a permanent energy services program for the Tribe. The original purpose of the DOE grant that funded this project was to determine the feasibility of creating a full-blown Yurok Tribal electric utility to buy and sell electric power and own and maintain all electric power infrastructure on the Reservation. The original project consultant found this opportunity to be infeasible for the Tribe. When SERC took over as project consultant, we took a different approach. We explored opportunities for the Tribe to develop its own renewable energy resources for use on the Reservation and/or off-Reservation sales as a means of generating revenue for the Tribe. We also looked at ways the Tribe can provide energy services to its members and how to fund such efforts. We identified opportunities for the development of renewable energy resources and energy services on the Yurok Reservation that fall into five basic categories: • Demand-side management – This refers to efforts to reduce energy use through energy efficiency and conservation measures. • Off-grid, facility and household scale renewable energy systems – These systems can provide electricity to individual homes and Tribal facilities in areas of the Reservation that do not currently have access to the electric utility grid. • Village scale, micro-grid renewable energy systems - These are larger scale systems that can provide electricity to interconnected groups of homes and Tribal facilities in areas of the Reservation that do not have access to the conventional electric grid. This will require the development of miniature electric grids to serve these interconnected facilities. • Medium to large scale renewable energy development for sale to the grid – In areas where viable renewable energy resources exist and there is access to the conventional electric utility grid, these resources can be developed and sold to the wholesale electricity market. • Facility scale, net metered renewable energy systems – These are renewable energy systems that provide power to individual households or facilities that are connected to conventional electric utility grid.

Engel, R. A.; Zoellick, J. J.

2007-06-30

398

Spectrum to space transformed fast terahertz imaging.  

PubMed

We present an imaging technique in which the broadband frequency information of terahertz (THz) pulses is transformed into spatial resolution. Efficient blazed diffractive gratings spread the individual frequency components over a wide and defined spatial range and f-theta optics are employed to focus the individual components onto a one-dimensional image-line. Measuring the time domain waveform of the THz waves allows therefore for a direct reconstruction of spatial sample characteristics as the spatial domain information is encoded in the terahertz spectrum. We will demonstrate terahertz imaging on selected samples with an improvement in acquisition speed up to two orders of magnitude. PMID:23038561

Schumann, Steffen; Jansen, Christian; Schwerdtfeger, Michael; Busch, Stefan; Peters, Ole; Scheller, Maik; Koch, Martin

2012-08-13

399

A power line data communication interface using spread spectrum technology in home automation  

SciTech Connect

Building automation technology is rapidly developing towards more reliable communication systems, devices that control electronic equipments. These equipment if controlled leads to efficient energy management, and savings on the monthly electricity bill. Power Line communication (PLC) has been one of the dreams of the electronics industry for decades, especially for building automation. It is the purpose of this paper to demonstrate communication methods among electronic control devices through an AC power line carrier within the buildings for more efficient energy control. The paper outlines methods of communication over a powerline, namely the X-10 and CE bus. It also introduces the spread spectrum technology as to increase speed to 100--150 times faster than the X-10 system. The powerline carrier has tremendous applications in the field of building automation. The paper presents an attempt to realize a smart house concept, so called, in which all home electronic devices from a coffee maker to a water heater microwave to chaos robots will be utilized by an intelligent network whenever one wishes to do so. The designed system may be applied very profitably to help in energy management for both customer and utility.

Shwehdi, M.H.; Khan, A.Z. [King Fahd Univ. of Petroleum and Minerals, Dhahran (Saudi Arabia). Dept. of Electrical Engineering] [King Fahd Univ. of Petroleum and Minerals, Dhahran (Saudi Arabia). Dept. of Electrical Engineering

1996-07-01

400

Spectrum of 3C273.  

National Technical Information Service (NTIS)

This article describes the radio frequency spectrum of 3C273 based primarily on two occultation observations made using the 1000 foot steerable radio telescope at Arecibo, Puerto Rico. The results presented show that although the spectrum of the total flu...

C. Hazard S. Gulkis A. D. Bray

1966-01-01

401

Bayesian Spectrum And Chirp Analysis  

Microsoft Academic Search

: We seek optimal methods of estimating power spectrum and chirp (frequency change)rate for the case that one has incomplete noisy data on values y(t) of a time series. The Schusterperiodogram turns out to be a "sufficient statistic" for the spectrum, a generalization playing thesame role for chirped signals. However, the optimal processing is not a linear filtering operation likethe

E. T. Jaynes; Wayman Crow

1987-01-01

402

Frequency Allocation; The Radio Spectrum.  

ERIC Educational Resources Information Center

The Federal Communications Commission (FCC) assigns segments of the radio spectrum to categories of users, and specific frequencies within each segment to individual users. Since demand for channel space exceeds supply, the process is complex. The radio spectrum can be compared to a long ruler: the portion from 10-540 kiloHertz has been set aside…

Federal Communications Commission, Washington, DC.

403

Collision Broadening of Rotational Spectrum.  

National Technical Information Service (NTIS)

The problem studied is the rotational absorption spectrum of linear molecules of moment inertia I in a simple nonpolar buffer gas. The focus is on the behavior of the spectrum as the buffer gas pressure and the associated collision frequency v is increase...

E. P. Gross J. Otieno-Malo

1971-01-01

404

Spectrum Analyzer and Analysis Method for Measuring Power and Wavelength of Electromagnetic Radiation.  

National Technical Information Service (NTIS)

A spectrum analyzer for analyzing electromagnetic radiation which may be utilized to determine the radiation wavelength and power. The analyzer includes a gas filled chamber which has a collimating lens through which radiation is injected, and a reflectiv...

F. M. Mako J. A. Pasour C. W. Roberson

1984-01-01

405

Spread Spectrum Transmission. Part 1: General Characteristics le Trasmissioni a Spettro Allargato. Parte 1: Caratteristiche Generali.  

National Technical Information Service (NTIS)

The design parameters characterizing data transmission techniques are discussed in order to identify the operating conditions favorable to the utilization of spread spectrum modulation. The larger band required may be compensated by the higher data densit...

S. Bonora G. Falciasecca M. Frullone

1982-01-01

406

Two-fold pricing for competitive spectrum sharing in cognitive wireless mesh networks  

Microsoft Academic Search

A market-based two-fold relay-spectrum pricing (TFRSP) scheme for competitive spectrum sharing in cognitive wireless mesh network is proposed. The TFRSP scheme can guarantee non-negative profit for each secondary user for a wide range of user utilities and pricing functions. We determine the relay and spectrum pricing functions according to traffic load and profit maximization. Simulation results show that, compared to

Xin Huang; Suili Feng; Feng Ke; Hongcheng Zhuang

2010-01-01

407

Purging the BackRoom Dealing: Secure Spectrum Auction Leveraging Paillier Cryptosystem  

Microsoft Academic Search

Microeconomics-inspired spectrum auctions can dramatically improve the spectrum utilization for wireless net- works to satisfy the ever increasing service demands. However, the back-room dealing (i.e., the frauds of the insincere auc- tioneer and the bid-rigging between the greedy bidders and the auctioneer) poses significant security challenges, and fails all existing secure auction designs to allocate spectrum bands when considering the

Miao Pan; Jinyuan Sun; Yuguang Fang

2011-01-01

408

Expected Utility Distributions for Flexible, Contingent Execution  

NASA Technical Reports Server (NTRS)

This paper presents a method for using expected utility distributions in the execution of flexible, contingent plans. A utility distribution maps the possible start times of an action to the expected utility of the plan suffix starting with that action. The contingent plan encodes a tree of possible courses of action and includes flexible temporal constraints and resource constraints. When execution reaches a branch point, the eligible option with the highest expected utility at that point in time is selected. The utility distributions make this selection sensitive to the runtime context, yet still efficient. Our approach uses predictions of action duration uncertainty as well as expectations of resource usage and availability to determine when an action can execute and with what probability. Execution windows and probabilities inevitably change as execution proceeds, but such changes do not invalidate the cached utility distributions, thus, dynamic updating of utility information is minimized.

Bresina, John L.; Washington, Richard

2000-01-01

409

Nanocrystalline dye-sensitized solar cell\\/copper indium gallium selenide thin-film tandem showing greater than 15% conversion efficiency  

Microsoft Academic Search

Multijunction stacked (tandem) solar cells can increase the overall photovoltaic conversion efficiency by optimal utilization of the solar spectrum in individual cells. We demonstrate that a photovoltaic tandem cell comprising a nanocrystalline dye-sensitized solar cell as a top cell for high-energy photons and a copper indium gallium selenide thin-film bottom cell for lower-energy photons produces AM 1.5 solar to electric

P. Liska; K. R. Thampi; M. Grätzel; D. Brémaud; D. Rudmann; H. M. Upadhyaya; A. N. Tiwari

2006-01-01

410

A Distributed Beamforming Approach for Enhanced Opportunistic Spectrum Access in Cognitive Radios  

Microsoft Academic Search

Cognitive radio is a powerful solution that can significantly improve the utilization of the precious limited radio spectrum. It allows secondary users (SUs) to opportunistically access spectral holes in the licensed spectrum without causing harmful interference to primary users (PUs). However, the secondary communication opportunity becomes extremely poor when primary systems are heavily loaded. In this paper, a distributed beamforming

Juan Liu; Wei Chen; Zhigang Cao; Ying Jun Zhang

2009-01-01

411

Using Spread-Spectrum Ranging Techniques for Position Tracking in a Virtual Environment  

Microsoft Academic Search

This paper proposes a radio frequency position tracking system for a virtual environ- ment utilizing spread-spectrum (SS) communication technology. The system utilizes two unique characteristics of spread-spectrum technology that are important to position track- ing in a virtual environment: code division multiple access (CDMA) and precision ranging. These characteristics allow multiple transmitter-receiver pairs and position accuracies in the millimeter range.

Steven R. Bible; Michael Zyda

1995-01-01

412

The eigenvalue spectrum of the Rayleigh equation for a plane shear layer  

NASA Technical Reports Server (NTRS)

The eigenvalue spectrum of the Rayleigh equation is examined using three different solution techniques. In particular, a simple second-order finite difference scheme and two spectral methods, the Chebyshev tau and Chebyshev collocation methods, are used to discretize the equation. All of the approximation methods are shown to be capable of predicting the discrete spectrum as well as the continuous spectrum associated with the critical point singularity for the Rayleigh equation. The global eigenvalue methods considered here provide an efficient way of obtaining either an approximation to the complete eigenvalue spectrum or initial guesses for a local shooting procedure for the discrete part of the spectrum.

Liou, William W.-W.; Morris, Philip J.

1992-01-01

413

Efficient conversion of solar energy to biomass and electricity  

PubMed Central

The Earth receives around 1000 W.m?2 of power from the Sun and only a fraction of this light energy is able to be converted to biomass (chemical energy) via the process of photosynthesis. Out of all photosynthetic organisms, microalgae, due to their fast growth rates and their ability to grow on non-arable land using saline water, have been identified as potential source of raw material for chemical energy production. Electrical energy can also be produced from this same solar resource via the use of photovoltaic modules. In this work we propose a novel method of combining both of these energy production processes to make full utilisation of the solar spectrum and increase the productivity of light-limited microalgae systems. These two methods of energy production would appear to compete for use of the same energy resource (sunlight) to produce either chemical or electrical energy. However, some groups of microalgae (i.e. Chlorophyta) only require the blue and red portions of the spectrum whereas photovoltaic devices can absorb strongly over the full range of visible light. This suggests that a combination of the two energy production systems would allow for a full utilization of the solar spectrum allowing both the production of chemical and electrical energy from the one facility making efficient use of available land and solar energy. In this work we propose to introduce a filter above the algae culture to modify the spectrum of light received by the algae and redirect parts of the spectrum to generate electricity. The electrical energy generated by this approach can then be directed to running ancillary systems or producing extra illumination for the growth of microalgae. We have modelled an approach whereby the productivity of light-limited microalgae systems can be improved by at least 4% through using an LED array to increase the total amount of illumination on the microalgae culture.

2014-01-01

414

Efficient conversion of solar energy to biomass and electricity.  

PubMed

The Earth receives around 1000 W.m(-2) of power from the Sun and only a fraction of this light energy is able to be converted to biomass (chemical energy) via the process of photosynthesis. Out of all photosynthetic organisms, microalgae, due to their fast growth rates and their ability to grow on non-arable land using saline water, have been identified as potential source of raw material for chemical energy production. Electrical energy can also be produced from this same solar resource via the use of photovoltaic modules. In this work we propose a novel method of combining both of these energy production processes to make full utilisation of the solar spectrum and increase the productivity of light-limited microalgae systems. These two methods of energy production would appear to compete for use of the same energy resource (sunlight) to produce either chemical or electrical energy. However, some groups of microalgae (i.e. Chlorophyta) only require the blue and red portions of the spectrum whereas photovoltaic devices can absorb strongly over the full range of visible light. This suggests that a combination of the two energy production systems would allow for a full utilization of the solar spectrum allowing both the production of chemical and electrical energy from the one facility making efficient use of available land and solar energy. In this work we propose to introduce a filter above the algae culture to modify the spectrum of light received by the algae and redirect parts of the spectrum to generate electricity. The electrical energy generated by this approach can then be directed to running ancillary systems or producing extra illumination for the growth of microalgae. We have modelled an approach whereby the productivity of light-limited microalgae systems can be improved by at least 4% through using an LED array to increase the total amount of illumination on the microalgae culture. PMID:24976951

Parlevliet, David; Moheimani, Navid Reza

2014-01-01

415

Stanford University: Dynamic Spectrum Management  

NSDL National Science Digital Library

Dynamic Spectrum Management (DSM) is a research program within the Space, Telecommunications, and Radioscience (STAR) Laboratory, a research group of the Department of Electrical Engineering of Stanford University. Researchers at DSM are investigating the potential for DSM to be used in multiuser environments, with particular emphasis on DSL and wireless transmission channels. Broadly speaking, topics covered through their research on DSM for DSL include: Channel Identification Methods, Spectrum Balancing, Vectored Transmission Methods, and Multiuser Detection. The website provides information on these different areas and links to related publications. The Tutorials section offers some papers and presentations explaining the basics of Dynamic Spectrum Management. A separate section includes papers on Standards Contributions.

Cioffi, John M.

2005-11-05

416

Compressed Wideband Spectrum Sensing Based on Discrete Cosine Transform  

PubMed Central

Discrete cosine transform (DCT) is a special type of transform which is widely used for compression of speech and image. However, its use for spectrum sensing has not yet received widespread attention. This paper aims to alleviate the sampling requirements of wideband spectrum sensing by utilizing the compressive sampling (CS) principle and exploiting the unique sparsity structure in the DCT domain. Compared with discrete Fourier transform (DFT), wideband communication signal has much sparser representation and easier implementation in DCT domain. Simulation result shows that the proposed DCT-CSS scheme outperforms the conventional DFT-CSS scheme in terms of MSE of reconstruction signal, detection probability, and computational complexity.

Wang, Yulin; Zhang, Gengxin

2014-01-01

417

Stepped-frequency processing by reconstruction of target reflectivity spectrum  

Microsoft Academic Search

This paper describes a processing technique for combining stepped-frequency waveforms efficiently to obtain higher range resolution. Essentially this method involves the reconstruction of a wider portion of the target's reflectivity spectrum by combining the individual spectra of the transmitted narrow-bandwidth pulses in the frequency domain. This paper describes the signal processing steps involved, and shows simulation results which validate and

Andrew J. Wilkinson; R. T. Lord; Michael R. Inggs

1998-01-01

418

Fourier Transform based DS\\/FH Spread Spectrum Receiver  

Microsoft Academic Search

An approach towards an efficient implementation of a spread spectrum receiver for wireless non- cellular home-systems is presented. Whereas conventional receivers apply some filtering after despread- ing to recover the transmitted data, here a Discrete Fourier transform is applied and its output is redirected to an application specific processor (ASP). As mathematical operations (Fourier transforms) play a key role in

Jack P. F. Glas; Sándor E. Skolnik

1994-01-01

419

Modal combination in response spectrum modal dynamic analysis  

SciTech Connect

UCRL-15910 does not give explicit requirements for combining the values of the resonse of individual modes in a response spectrum modal dynamic analysis. Since UCRL-15910 references ASE 4-86, modal combination methods given in ASCE 4-86 are described in this paper. Efficient use of typical dynamic analysis computer programs while complying with ASCE 4-86 is also described.

Hammond, C.R.; Singhal, M.K.

1993-09-01

420

Is Emotion Recognition Impaired in Individuals with Autism Spectrum Disorders?  

ERIC Educational Resources Information Center

Researchers have argued that individuals with autism spectrum disorders (ASDs) use an effortful "systematizing" process to recognize emotion expressions, whereas typically developing (TD) individuals use a more holistic process. If this is the case, individuals with ASDs should show slower and less efficient emotion recognition, particularly for…

Tracy, Jessica L.; Robins, Richard W.; Schriber, Roberta A.; Solomon, Marjorie

2011-01-01

421

SMMA Alpha Spectrum Deconvolution Code.  

National Technical Information Service (NTIS)

We performed a computer code ''SMMA'' able to deconvoluate routinely alpha spectrometry spectrum including up to seven pics groups. The tailing is carried out by using homographic and exponential functions. (ERA citation 09:035869)

F. Amoudry

1983-01-01

422

The geoid spectrum from altimetry  

NASA Technical Reports Server (NTRS)

Satellite altimetry information from the world's major oceans was analyzed to arrive at a geoid power spectrum. Using the equivalent of about 7 revolutions of data (mostly from GEOS-3) the power spectrum of the sea surface generally follows the expected values from Kaula's rule applied to the geoid. Analysis of overlapping altimetry arcs (and oceanographic data) shows that the surface spectrum is dominated by the geoid to about 500 cycles (40 km half wavelength) but that sea state departures are significant starting at about 250 cycles (80 km). Estimates of geopotential variances from a derived (smooth) geoid spectrum show significantly less power than Kaula's rule to about 60 cycles, but somewhat more from there to about 400 cycles. At less than 40 km half wavelength, the total power in the marine geoid may be negligible.

Wagner, C. A.

1978-01-01

423

The ultrahigh energy photon spectrum  

NASA Technical Reports Server (NTRS)

Results are made of a numerical calculation of the ultrahigh energy photon spectrum. After assuming that the ultrahigh energy cosmic-ray nucleons are universal, calculations are made without resorting to the previously employed delta function approximation.

Stecker, F. W.; Bredekamp, J. H.

1972-01-01

424

The Spectrum of Potassium Hydride  

Microsoft Academic Search

The 1Sigma-->1Sigma molecular spectrum extending from 4100A to 6600A has been photographed with prism spectrographs with a d.c. potassium arc in hydrogen as source. In absorption spectrographs, also attempted, the bands were masked by alkali bands except in a short region, 4600A to 4800A. The spectrum is of the many-lined type. Analysis disclosed 29 bands falling into five v' progressions.

G. M. Almy; C. D. Hause

1932-01-01

425

The laboratory test utilization management toolbox  

PubMed Central

Efficiently managing laboratory test utilization requires both ensuring adequate utilization of needed tests in some patients and discouraging superfluous tests in other patients. After the difficult clinical decision is made to define the patients that do and do not need a test, a wealth of interventions are available to the clinician and laboratorian to help guide appropriate utilization. These interventions are collectively referred to here as the utilization management toolbox. Experience has shown that some tools in the toolbox are weak and other are strong, and that tools are most effective when many are used simultaneously. While the outcomes of utilization management studies are not always as concrete as may be desired, what data is available in the literature indicate that strong utilization management interventions are safe and effective measures to improve patient health and reduce waste in an era of increasing financial pressure.

Baird, Geoffrey

2014-01-01

426

High efficiency RCCI combustion  

NASA Astrophysics Data System (ADS)

An experimental investigation of the pragmatic limits of Reactivity Controlled Compression Ignition (RCCI) engine efficiency was performed. The study utilized engine experiments combined with zero-dimensional modeling. Initially, simulations were used to suggest conditions of high engine efficiency with RCCI. Preliminary simulations suggested that high efficiency could be obtained by using a very dilute charge with a high compression ratio. Moreover, the preliminary simulations further suggested that with simultaneous 50% reductions in heat transfer and incomplete combustion, 60% gross thermal efficiency may be achievable with RCCI. Following the initial simulations, experiments to investigate the combustion process, fuel effects, and methods to reduce heat transfer and incomplete combustion reduction were conducted. The results demonstrated that the engine cycle and combustion process are linked, and if high efficiency is to be had, then the combustion event must be tailored to the initial cycle conditions. It was found that reductions to engine heat transfer are a key enabler to increasing engine efficiency. In addition, it was found that the piston oil jet gallery cooling in RCCI may be unnecessary, as it had a negative impact on efficiency. Without piston oil gallery cooling, it was found that RCCI was nearly adiabatic, achieving 95% of the theoretical maximum cycle efficiency (air standard Otto cycle efficiency).

Splitter, Derek A.

427

Raman Spectrum of Strained Single Layer Graphene  

NASA Astrophysics Data System (ADS)

Two-dimensional single layer graphene (SLG) films are very attractive due to their unique electrical and optical properties. In this work, silicon nitride, silicon oxide and polyimide are used to induce strain in SLG sheets. Micro-Raman spectra reveal the evolution of graphene feature peaks under various stress conditions. Different peak position, width and shape are observed due to different stress type, level and direction. Changes of the second order D peaks show that strain affects not only the phonon spectrum but also the electron band through a double resonant Raman process. Relative intensity changes between D and G bands indicate that defects are introduced into graphene during some of the deposition processes, which usually are not observed in spin-coated SLG samples. Strain effects also can be utilized to further modify the electron band structure of graphene.

Wang, Minsheng; Han, Song; Wang, Kang L.

2008-03-01

428

NEUROIMMUNE MECHANISMS IN FETAL ALCOHOL SPECTRUM DISORDER  

PubMed Central

Fetal alcohol spectrum disorder (FASD) is a major health concern worldwide and results from maternal consumption of alcohol during pregnancy. It produces tremendous individual, social, and economic losses. This review will first summarize the structural, functional and behavior changes seen in FASD. The development of the neuroimmune system will be then be described with particular emphasis on the role of microglial cells in the normal regulation of homeostatic function in the central nervous system (CNS) including synaptic transmission. The impact of alcohol on the neuroimmune system in the developing CNS will be discussed in the context of several key immune molecules and signaling pathways involved in neuroimmune mechanisms that contribute to FASD. This review concludes with a summary of the development of early therapeutic approaches utilizing immunosuppressive drugs to target alcohol-induced pathologies. The significant role played by neuroimmune mechanisms in alcohol addiction and pathology provides a focus for future research aimed at understanding and treating the consequences of FASD.

Kane, Cynthia J. M.; Phelan, Kevin D.; Drew, Paul D.

2012-01-01

429

Advances in biological microanalysis using event streamed spectrum imaging and programmed beam acquisition  

Microsoft Academic Search

The current trend of x-ray mapping in Electron Probe X-ray Microanalysis (EPXMA) is toward full spectrum collection, or spectrum\\u000a imaging [1]. Spectrum imaging is the collection and spatial registration of all x-ray events, yielding a spectral data cube.\\u000a Recent developments in spectral analytical techniques have greatly improved the efficiency and precision of data handling\\u000a from quantitative chemical images; principal component

Peter Ingram; Scott Davilla; Ann LeFurgey

430

A graph spectrum based geometric biclustering algorithm.  

PubMed

Biclustering is capable of performing simultaneous clustering on two dimensions of a data matrix and has many applications in pattern classification. For example, in microarray experiments, a subset of genes is co-expressed in a subset of conditions, and biclustering algorithms can be used to detect the coherent patterns in the data for further analysis of function. In this paper, we present a graph spectrum based geometric biclustering (GSGBC) algorithm. In the geometrical view, biclusters can be seen as different linear geometrical patterns in high dimensional spaces. Based on this, the modified Hough transform is used to find the Hough vector (HV) corresponding to sub-bicluster patterns in 2D spaces. A graph can be built regarding each HV as a node. The graph spectrum is utilized to identify the eigengroups in which the sub-biclusters are grouped naturally to produce larger biclusters. Through a comparative study, we find that the GSGBC achieves as good a result as GBC and outperforms other kinds of biclustering algorithms. Also, compared with the original geometrical biclustering algorithm, it reduces the computing time complexity significantly. We also show that biologically meaningful biclusters can be identified by our method from real microarray gene expression data. PMID:23079285

Wang, Doris Z; Yan, Hong

2013-01-21

431

The Spectrum of Autism Spectrum Disorder: A Spectrum of Needs, Services, and Challenges  

Microsoft Academic Search

The dramatic rise in the diagnosis of autism spectrum disorders (ASDs) has resulted in a significant explosion in visibility\\u000a and a substantial increase in the understanding of this complex group of disorders. Over the last decade, what was once defined\\u000a only as “autism” has become a spectrum of neurodevelopmental disorders, with variable presentations and levels of impairment\\u000a that requires an

Vanessa K. JensenSarah; Sarah Cain Spannagel

2011-01-01

432

Evaluation in a competitive utility environment: the threat of confidentiality.  

National Technical Information Service (NTIS)

Utilities have become concerned that their competitors will desire access to energy-related data--including energy-efficiency data collected by utilities from their energy- efficiency programs--that they may regard as proprietary or confidential. In the f...

E. Vine

1997-01-01

433

Miscellaneous Mathematical Utilities  

NSDL National Science Digital Library

Several online mathematical utilities intended for college and university students (math, physics, engineering, etc. students). Numerical utilities to solve (among others): N Equations in N Unknowns, Eigenvalues and Eigenvectors, Roots of Functions, and Numerical Integration. More utilities are constantly being added.

2007-08-09

434

Progress in full-spectrum polarized lighting systems  

SciTech Connect

It is now possible to provide interior illumination that is indistinguishable from natural daylight. Such technology is called Full-Spectrum Polarized Lighting, which combines full spectrum fluorescent lamps with multi-layer polarized diffusers. Application of Full-Spectrum Polarized Lighting will necessitate a revolution in lighting design, as present practice as promulgated through IES handbooks, reference manuals, and recommended practices must be discarded and replaced by new materials that will be adopted by the IES. A newly patented multi-layer polarized diffuser that will polarize ultraviolet light as well as visible light soon will be placed on the market. Thus, the problems from unpolarized ultraviolet light from glare can be solved once and for all. Newly developed full-spectrum fluorescent lamps are 35% more visually efficient than cool-white or T-8 lamps, making these technologies obsolete as well. Full-Spectrum Polarized Lighting is the most energy efficient technology available, with potential savings of 80% on most retrofit work. Design of interior illumination at .25 to .5 watts per square foot has been achieved in a number of installations on Long Island.

Karpen, D.

1995-12-31

435

On the Fluctuation Spectrum of a Vlasov Plasma  

NASA Astrophysics Data System (ADS)

The use of functional integrals for the evaluation of homogeneous turbulent fluid spectra dates to the early work of T. D. Lee and L. Onsager. For example, such statistical mechanics techniques have been applied to two-dimensional Euler fluid equations(D. Montgomery and R. Kraichnan, Rep. Prog. Phys. 43), 35 (1979). by analyzing point vortices or, alternatively, by Fourier transforming the vorticity and treating the resulting Fourier amplitudes as particle degrees of freedom. We, however, obtain the turbulent fluctuation spectrum for a Vlasov plasma by expanding in the eigenfunctions of the continuous spectrum --- van Kampen modes. We calculate the functional integrals exactly obtaining a composite spectrum with screening and particle contributions. The methods employed are of general utility and can also be applied to inhomogeneous fluid systems such as shear flow in a channel.

Morrison, P. J.; Shadwick, B. A.

1998-11-01

436

A random access algorithm for frequency hopped spread spectrum packet radio networks  

Microsoft Academic Search

The authors consider packet radio multi-user spread-spectrum environments, where frequency hopping spread spectrum techniques are deployed for protection against intelligent adversaries. When the users in such environments are mobile and bursty, random access frequency hopping transmission algorithms should be adopted, for efficiency in throughput and delay control. This paper proposes and analyzes such an algorithm, named Collision Resolution Algorithm for

M. Georgiopoulos; P. Papantoni-Kazakos

1986-01-01

437

A Noise-Robust FFT-Based Auditory Spectrum With Application in Audio Classification  

Microsoft Academic Search

In this paper, we investigate the noise robustness of Wang and Shamma's early auditory (EA) model for the calculation of an auditory spectrum in audio classification applications. First, a stochastic analysis is conducted wherein an approximate expres- sion of the auditory spectrum is derived to justify the noise-sup- pression property of the EA model. Second, we present an efficient fast

Wei Chu; BenoÎt Champagne

2008-01-01

438

Carbon utilization in fluidized-bed combustion systems  

SciTech Connect

The objectives of the work reported were to systematically evaluate the available data in the literature on carbon utilization and/or combustion efficiency in fluidized combustion systems, and to generate additional data where needed in a bench scale combustor. Trends in carbon utilization as a function of design and operating parameters are presented. Factors affecting the carbon utilization are identified and discussed. (LEW)

Krishnan, R.P.; Zimmerman, G.P.; Lackey, M.E.; Daw, C.S.

1983-05-01

439

The spectrum of HD46223  

NASA Astrophysics Data System (ADS)

The spectrum of HD46223 was established from the optical to the far UV and normalized by the spectrum of a non-reddened star of same spectral type. The resulting spectrum is separated into two components. One is the direct starlight. The second is an additional component of light scattered at small angles. In the optical the spectrum is dominated by direct starlight which decreases exponentially due to the linear extinction ? e-2E(B-V)/?. Scattered light begins to be noticeable in the near-UV. The near-UV rise of the scattered light is interrupted in the 2200 Å bump region. The wavelength dependence of the scattered light is established in the far-UV, where scattered light dominates the extinction curve. A 1/ ?4 dependence is found, proving the presence of grains small compared to UV wavelengths. The mathematic expressions of the different components mentioned above give a good fit to the extinction curve in the direction of the star. On a mathematic standpoint the fit can be completed by a Lorentzien for the 2200 Å bump region. The physical interpretation of the bump may be more difficult to achieve since the paper shows the possibility that only scattered light is extinguished in the bump region. Consequences for the grain size distribution which is necessary to explain the different aspects of scattering in interstellar clouds, for the value of RV, and problems raised by this interpretation of the spectrum of HD46223, are considered at the end of this paper.

Zagury, Frédéric

2001-10-01

440

Spectrum Savings from High Performance Recording and Playback Onboard the Test Article.  

National Technical Information Service (NTIS)

The Test Resource Management Center's (TRMC) Spectrum Efficient Technologies (SET) S&T program is sponsoring development of the Enhanced Query Data Recorder (EQDR), a network flight recorder that is intended to meet the future needs of the networked telem...

A. M. Mazzario M. A. Wigent

2013-01-01

441

Enol Ethers as Substrates for Efficient Z- and Enantioselective Ring-Opening/Cross-Metathesis Reactions Promoted by Stereogenic-at-Mo Complexes. Utility in Chemical Synthesis and Mechanistic Attributes  

PubMed Central

The first examples of catalytic enantioselective ring-opening/cross-metathesis (EROCM) reactions that involve enol ethers are reported. Specifically, we demonstrate that catalytic EROCM of several oxa- and azabicycles, cyclobutenes and a cyclopropene with an alkyl- or aryl-substituted enol ether proceed readily in the presence of a stereogenic-at-Mo monopyrrolide-monoaryloxide. In some instances, as little as 0.15 mol % of the catalytically active alkylidene is sufficient to promote complete conversion within 10 minutes. The desired products are formed in up to 90% yield and >99:1 enantiomeric ratio (er) with the disubstituted enol ether generated in >90% Z selectivity. The enol ether of the enantiomerically enriched products can be easily differentiated from the terminal alkene through a number of functionalization procedures that lead to the formation of useful intermediates for chemical synthesis (e.g., efficient acid hydrolysis to afford the enantiomerically enriched carboxaldehyde). In certain cases, enantioselectivity is strongly dependent on enol ether concentration: larger equivalents of the cross partner leads to the formation of products of high enantiomeric purity (versus near racemic products with one equivale